Case Report

A 60-year-old man with a history of Hodgkin lymphoma that had been treated with chemotherapy 6 years prior presented to our dermatology clinic with a persistent pruritic rash on the back, abdomen, and bilateral arms and legs. The eruption initially began as localized discrete lesions on the lower back 1 year prior to the current presentation; at that time a diagnosis of psoriasis was made at an outside dermatology clinic, and treatment with mometasone furoate cream was initiated. Despite the patient’s compliance with this treatment, the lesions did not resolve and began spreading to the arms, legs, chest, and abdomen. His current medications included lisinopril, escitalopram, aspirin, and omeprazole.

On presentation to our clinic, physical examination revealed round, scaly, pink plaques and tumors of variable sizes (3–10 cm) distributed asymmetrically on the chest, back, abdomen, arms, and legs (Figure 1). The lesions were grouped in well-defined areas encompassing approximately 30% of the body surface area. No lymphadenopathy was appreciated. In vivo reflectance confocal microscopy (RCM) performed on one of the lesions revealed disarray of the epidermis with small, weakly refractile, round to oval cells scattered within the spinous layer and dermoepidermal junction (Figure 2). Additionally, these weakly refractile, round to oval cells also were seen in vesiclelike dark spaces, and hyporefractile basal cells were appreciated surrounding the dermal papillae. Mycosis fungoides (MF) was diagnosed following correlation of the RCM findings with the clinical picture.

A biopsy was performed, with pathologic examination confirming the diagnosis of tumor-stage MF. Parakeratosis with epidermotropism of lymphocytes was noted along the basal layer and into the spinous layer of the epidermis (Figure 3). Underlying the epidermis there was a dense mononuclear infiltrate and conspicuous eosinophils extending to the deeper reticular dermis. The infiltrating cells had cerebriform nuclei and large pale cytoplasm. On immunostaining, the lymphocytes were positive for CD3 and CD4, and negative for CD5, CD7, and CD8. The patient was referred to the oncology department for disease management. Staging workup including computed tomography, flow cytometry, and T-cell receptor gene rearrangement were consistent with tumor-stage MF (T3N0M0B0).

Comment

Clinical Presentation of MF
Mycosis fungoides, a non-Hodgkin lymphoma of T-cell origin, is the most commonly diagnosed cutaneous lymphoma worldwide.¹ It has an annual incidence of approximately 0.36 per 100,000 persons, and this number continues to rise.^2,3 The median age of diagnosis is 55 to 60 years, and MF occurs twice as often in men versus women.⁴

The clinical presentation of MF varies and is classified by stages including patches, plaques, tumors, and erythroderma.⁵ Classically, MF is slowly progressive and begins as pruritic erythematous patches that have a predilection for non–sun-exposed areas of the skin. Over time, these patches may evolve into plaques and tumors. Early or patch-stage MF often presents as well-demarcated lesions of various sizes and shapes that tend to enlarge.⁶ These lesions may resemble eczema or psoriasis if there is scaling, such as in our patient. At the tumor stage, flat or dome-shaped nodules that may vary in color and are deeper than plaques begin to appear. Ulcerations, which were absent in our case, may often be seen.

Because of the diverse clinical manifestations of MF, which can mimic other common dermatoses, diagnosis often is challenging for clinicians. Furthermore, histology can yield nonspecific diagnostic results and may even resemble chronic inflammatory dermatoses.⁷ As a result, patients frequently are subjected to multiple skin biopsies to establish the diagnosis,⁸ and diagnosis may be delayed, with the median time from onset of skin symptoms to diagnosis being approximately 6 years.⁹

Reflectance Confocal Microscopy
In vivo RCM is a noninvasive technique that allows visualization of the skin at a cellular level and recently has been evaluated as a diagnostic tool for many skin conditions.^10,11 Reflectance confocal microscopy findings have been well established for many cutaneous malignancies as well as inflammatory conditions such as psoriasis and atopic dermatitis.^12,13 Specifically, 2 preliminary descriptive studies utilized RCM to visualize the characteristic features of MF in vivo.^14,15 These studies reported the histopathologic correlation of RCM findings in biopsy-proven MF lesions. Consistent in all stages of MF is the presence of small, weakly refractile, round to oval cells within the spinous layer that correlate with atypical lymphocytes, in addition to hyporefractile basal cells surrounding the dermal papillae. Patch-stage MF lesions have more subtle epidermal findings compared to plaque-stage lesions, which tend to have more prominent vesiclelike dark spaces filled with collections of monomorphous, weakly refractile, round to oval cells corresponding with Pautrier microabscesses and evidence of spongiosis.^14,15 The first descriptive study of RCM in the diagnosis of MF failed to identify features of tumor-stage MF that would distinguish it from patch- or plaque-stage disease. The investigators also stated that deep nodular collections of atypical lymphocytes seen on histopathology in tumor-stage MF were missed on RCM evaluation.¹⁴ Furthermore, the second descriptive study of RCM and MF, which included 2 patients with tumor-stage disease, also failed to differentiate tumor-stage MF from the patch or plaque stages.¹⁵

Because of these 2 descriptive studies, a pilot study was conducted to determine the applicability and reproducibility of RCM findings for MF diagnosis.¹⁶ Two blinded confocalists were asked to diagnose RCM images as MF when compared to either normal skin or a variety of lymphoproliferative disorders. Of 15 patients, the confocalists correctly diagnosed MF in 84% and 90% of cases, respectively. Additionally, they reported the specificity and sensitivity of the following RCM features in the diagnosis of MF: spongiosis, 88.9% and 94.7%; loss of demarcation, 88.9% and 94.7%; disarray of the epidermis, 77.8% and 89.5%; hyporefractile rings, 88.9% and 78.9%; junctional atypical lymphocytes, 100% and 73.7%; and vesiclelike structures (Pautrier microabscesses), 100% and 73.7%. Importantly, this study did not evaluate the specificity and sensitivity of MF diagnosis compared to other eczematous or inflammatory conditions that may share similar RCM findings; therefore, these results are not generalizable, and many of the RCM findings characteristically seen in MF are not specific to its diagnosis.¹⁶

One study assessed the diagnostic accuracy of RCM in evaluating erythematosquamous diseases including MF, psoriasis, contact dermatitis, discoid lupus, and subacute cutaneous lupus.¹⁷ In this study, 3 blinded confocalists achieved a 95.41% and 92.89% specificity and 89.13% and 63.33% sensitivity for psoriasis and MF, respectively. Typical features of psoriasis on RCM included parakeratosis, reduction or absence of the granular layer, papillomatosis, acanthosis with normal honeycomb pattern of the epidermis, and dilated vessels in the upper dermis. Features that were more specific to MF included epidermotropic atypical lymphocytes, interface dermatitis, pleomorphic tumor cells, and dendritic cells.¹⁷ However, atypical lymphocytes and interface dermatitis also may be seen in cutaneous lupus; therefore, additional studies are still needed to validate RCM’s utility in differentiating between erythematosquamous skin diseases, including psoriasis, cutaneous lupus, and MF. Currently, RCM findings must be interpreted in conjunction with the clinical and histologic picture.

Importantly, RCM also is limited when evaluating MF due to its limited depth of visualization, as it allows imaging only to the superficial papillary dermis. Furthermore, any infiltrative process such as epidermal hyperplasia, spongiosis, or scaling, which can be seen in MF, may further impair the imaging quality of the deeper dermis.

Conclusion

Despite its limitations, RCM has the potential to be advantageous in evaluating skin lesions suspicious for MF in real time and is a promising technology for a quick noninvasive bedside adjunct tool. Its utility in selecting the optimal site for biopsy for better yield of histopathologic results in suspected MF cases has been demonstrated.¹⁶ However, large-scale studies still are needed to evaluate RCM in the diagnosis of the wide diversity of MF lesions as well as its efficacy in selecting optimal biopsy sites.

Case Report

A 60-year-old man with a history of Hodgkin lymphoma that had been treated with chemotherapy 6 years prior presented to our dermatology clinic with a persistent pruritic rash on the back, abdomen, and bilateral arms and legs. The eruption initially began as localized discrete lesions on the lower back 1 year prior to the current presentation; at that time a diagnosis of psoriasis was made at an outside dermatology clinic, and treatment with mometasone furoate cream was initiated. Despite the patient’s compliance with this treatment, the lesions did not resolve and began spreading to the arms, legs, chest, and abdomen. His current medications included lisinopril, escitalopram, aspirin, and omeprazole.

On presentation to our clinic, physical examination revealed round, scaly, pink plaques and tumors of variable sizes (3–10 cm) distributed asymmetrically on the chest, back, abdomen, arms, and legs (Figure 1). The lesions were grouped in well-defined areas encompassing approximately 30% of the body surface area. No lymphadenopathy was appreciated. In vivo reflectance confocal microscopy (RCM) performed on one of the lesions revealed disarray of the epidermis with small, weakly refractile, round to oval cells scattered within the spinous layer and dermoepidermal junction (Figure 2). Additionally, these weakly refractile, round to oval cells also were seen in vesiclelike dark spaces, and hyporefractile basal cells were appreciated surrounding the dermal papillae. Mycosis fungoides (MF) was diagnosed following correlation of the RCM findings with the clinical picture.

A biopsy was performed, with pathologic examination confirming the diagnosis of tumor-stage MF. Parakeratosis with epidermotropism of lymphocytes was noted along the basal layer and into the spinous layer of the epidermis (Figure 3). Underlying the epidermis there was a dense mononuclear infiltrate and conspicuous eosinophils extending to the deeper reticular dermis. The infiltrating cells had cerebriform nuclei and large pale cytoplasm. On immunostaining, the lymphocytes were positive for CD3 and CD4, and negative for CD5, CD7, and CD8. The patient was referred to the oncology department for disease management. Staging workup including computed tomography, flow cytometry, and T-cell receptor gene rearrangement were consistent with tumor-stage MF (T3N0M0B0).

Comment

Clinical Presentation of MF
Mycosis fungoides, a non-Hodgkin lymphoma of T-cell origin, is the most commonly diagnosed cutaneous lymphoma worldwide.¹ It has an annual incidence of approximately 0.36 per 100,000 persons, and this number continues to rise.^2,3 The median age of diagnosis is 55 to 60 years, and MF occurs twice as often in men versus women.⁴

The clinical presentation of MF varies and is classified by stages including patches, plaques, tumors, and erythroderma.⁵ Classically, MF is slowly progressive and begins as pruritic erythematous patches that have a predilection for non–sun-exposed areas of the skin. Over time, these patches may evolve into plaques and tumors. Early or patch-stage MF often presents as well-demarcated lesions of various sizes and shapes that tend to enlarge.⁶ These lesions may resemble eczema or psoriasis if there is scaling, such as in our patient. At the tumor stage, flat or dome-shaped nodules that may vary in color and are deeper than plaques begin to appear. Ulcerations, which were absent in our case, may often be seen.

Because of the diverse clinical manifestations of MF, which can mimic other common dermatoses, diagnosis often is challenging for clinicians. Furthermore, histology can yield nonspecific diagnostic results and may even resemble chronic inflammatory dermatoses.⁷ As a result, patients frequently are subjected to multiple skin biopsies to establish the diagnosis,⁸ and diagnosis may be delayed, with the median time from onset of skin symptoms to diagnosis being approximately 6 years.⁹

Reflectance Confocal Microscopy
In vivo RCM is a noninvasive technique that allows visualization of the skin at a cellular level and recently has been evaluated as a diagnostic tool for many skin conditions.^10,11 Reflectance confocal microscopy findings have been well established for many cutaneous malignancies as well as inflammatory conditions such as psoriasis and atopic dermatitis.^12,13 Specifically, 2 preliminary descriptive studies utilized RCM to visualize the characteristic features of MF in vivo.^14,15 These studies reported the histopathologic correlation of RCM findings in biopsy-proven MF lesions. Consistent in all stages of MF is the presence of small, weakly refractile, round to oval cells within the spinous layer that correlate with atypical lymphocytes, in addition to hyporefractile basal cells surrounding the dermal papillae. Patch-stage MF lesions have more subtle epidermal findings compared to plaque-stage lesions, which tend to have more prominent vesiclelike dark spaces filled with collections of monomorphous, weakly refractile, round to oval cells corresponding with Pautrier microabscesses and evidence of spongiosis.^14,15 The first descriptive study of RCM in the diagnosis of MF failed to identify features of tumor-stage MF that would distinguish it from patch- or plaque-stage disease. The investigators also stated that deep nodular collections of atypical lymphocytes seen on histopathology in tumor-stage MF were missed on RCM evaluation.¹⁴ Furthermore, the second descriptive study of RCM and MF, which included 2 patients with tumor-stage disease, also failed to differentiate tumor-stage MF from the patch or plaque stages.¹⁵

Because of these 2 descriptive studies, a pilot study was conducted to determine the applicability and reproducibility of RCM findings for MF diagnosis.¹⁶ Two blinded confocalists were asked to diagnose RCM images as MF when compared to either normal skin or a variety of lymphoproliferative disorders. Of 15 patients, the confocalists correctly diagnosed MF in 84% and 90% of cases, respectively. Additionally, they reported the specificity and sensitivity of the following RCM features in the diagnosis of MF: spongiosis, 88.9% and 94.7%; loss of demarcation, 88.9% and 94.7%; disarray of the epidermis, 77.8% and 89.5%; hyporefractile rings, 88.9% and 78.9%; junctional atypical lymphocytes, 100% and 73.7%; and vesiclelike structures (Pautrier microabscesses), 100% and 73.7%. Importantly, this study did not evaluate the specificity and sensitivity of MF diagnosis compared to other eczematous or inflammatory conditions that may share similar RCM findings; therefore, these results are not generalizable, and many of the RCM findings characteristically seen in MF are not specific to its diagnosis.¹⁶

One study assessed the diagnostic accuracy of RCM in evaluating erythematosquamous diseases including MF, psoriasis, contact dermatitis, discoid lupus, and subacute cutaneous lupus.¹⁷ In this study, 3 blinded confocalists achieved a 95.41% and 92.89% specificity and 89.13% and 63.33% sensitivity for psoriasis and MF, respectively. Typical features of psoriasis on RCM included parakeratosis, reduction or absence of the granular layer, papillomatosis, acanthosis with normal honeycomb pattern of the epidermis, and dilated vessels in the upper dermis. Features that were more specific to MF included epidermotropic atypical lymphocytes, interface dermatitis, pleomorphic tumor cells, and dendritic cells.¹⁷ However, atypical lymphocytes and interface dermatitis also may be seen in cutaneous lupus; therefore, additional studies are still needed to validate RCM’s utility in differentiating between erythematosquamous skin diseases, including psoriasis, cutaneous lupus, and MF. Currently, RCM findings must be interpreted in conjunction with the clinical and histologic picture.

Importantly, RCM also is limited when evaluating MF due to its limited depth of visualization, as it allows imaging only to the superficial papillary dermis. Furthermore, any infiltrative process such as epidermal hyperplasia, spongiosis, or scaling, which can be seen in MF, may further impair the imaging quality of the deeper dermis.

Conclusion

Despite its limitations, RCM has the potential to be advantageous in evaluating skin lesions suspicious for MF in real time and is a promising technology for a quick noninvasive bedside adjunct tool. Its utility in selecting the optimal site for biopsy for better yield of histopathologic results in suspected MF cases has been demonstrated.¹⁶ However, large-scale studies still are needed to evaluate RCM in the diagnosis of the wide diversity of MF lesions as well as its efficacy in selecting optimal biopsy sites.

Case Report

A 60-year-old man with a history of Hodgkin lymphoma that had been treated with chemotherapy 6 years prior presented to our dermatology clinic with a persistent pruritic rash on the back, abdomen, and bilateral arms and legs. The eruption initially began as localized discrete lesions on the lower back 1 year prior to the current presentation; at that time a diagnosis of psoriasis was made at an outside dermatology clinic, and treatment with mometasone furoate cream was initiated. Despite the patient’s compliance with this treatment, the lesions did not resolve and began spreading to the arms, legs, chest, and abdomen. His current medications included lisinopril, escitalopram, aspirin, and omeprazole.

On presentation to our clinic, physical examination revealed round, scaly, pink plaques and tumors of variable sizes (3–10 cm) distributed asymmetrically on the chest, back, abdomen, arms, and legs (Figure 1). The lesions were grouped in well-defined areas encompassing approximately 30% of the body surface area. No lymphadenopathy was appreciated. In vivo reflectance confocal microscopy (RCM) performed on one of the lesions revealed disarray of the epidermis with small, weakly refractile, round to oval cells scattered within the spinous layer and dermoepidermal junction (Figure 2). Additionally, these weakly refractile, round to oval cells also were seen in vesiclelike dark spaces, and hyporefractile basal cells were appreciated surrounding the dermal papillae. Mycosis fungoides (MF) was diagnosed following correlation of the RCM findings with the clinical picture.

A biopsy was performed, with pathologic examination confirming the diagnosis of tumor-stage MF. Parakeratosis with epidermotropism of lymphocytes was noted along the basal layer and into the spinous layer of the epidermis (Figure 3). Underlying the epidermis there was a dense mononuclear infiltrate and conspicuous eosinophils extending to the deeper reticular dermis. The infiltrating cells had cerebriform nuclei and large pale cytoplasm. On immunostaining, the lymphocytes were positive for CD3 and CD4, and negative for CD5, CD7, and CD8. The patient was referred to the oncology department for disease management. Staging workup including computed tomography, flow cytometry, and T-cell receptor gene rearrangement were consistent with tumor-stage MF (T3N0M0B0).

Comment

Clinical Presentation of MF
Mycosis fungoides, a non-Hodgkin lymphoma of T-cell origin, is the most commonly diagnosed cutaneous lymphoma worldwide.¹ It has an annual incidence of approximately 0.36 per 100,000 persons, and this number continues to rise.^2,3 The median age of diagnosis is 55 to 60 years, and MF occurs twice as often in men versus women.⁴

The clinical presentation of MF varies and is classified by stages including patches, plaques, tumors, and erythroderma.⁵ Classically, MF is slowly progressive and begins as pruritic erythematous patches that have a predilection for non–sun-exposed areas of the skin. Over time, these patches may evolve into plaques and tumors. Early or patch-stage MF often presents as well-demarcated lesions of various sizes and shapes that tend to enlarge.⁶ These lesions may resemble eczema or psoriasis if there is scaling, such as in our patient. At the tumor stage, flat or dome-shaped nodules that may vary in color and are deeper than plaques begin to appear. Ulcerations, which were absent in our case, may often be seen.

Because of the diverse clinical manifestations of MF, which can mimic other common dermatoses, diagnosis often is challenging for clinicians. Furthermore, histology can yield nonspecific diagnostic results and may even resemble chronic inflammatory dermatoses.⁷ As a result, patients frequently are subjected to multiple skin biopsies to establish the diagnosis,⁸ and diagnosis may be delayed, with the median time from onset of skin symptoms to diagnosis being approximately 6 years.⁹

Reflectance Confocal Microscopy
In vivo RCM is a noninvasive technique that allows visualization of the skin at a cellular level and recently has been evaluated as a diagnostic tool for many skin conditions.^10,11 Reflectance confocal microscopy findings have been well established for many cutaneous malignancies as well as inflammatory conditions such as psoriasis and atopic dermatitis.^12,13 Specifically, 2 preliminary descriptive studies utilized RCM to visualize the characteristic features of MF in vivo.^14,15 These studies reported the histopathologic correlation of RCM findings in biopsy-proven MF lesions. Consistent in all stages of MF is the presence of small, weakly refractile, round to oval cells within the spinous layer that correlate with atypical lymphocytes, in addition to hyporefractile basal cells surrounding the dermal papillae. Patch-stage MF lesions have more subtle epidermal findings compared to plaque-stage lesions, which tend to have more prominent vesiclelike dark spaces filled with collections of monomorphous, weakly refractile, round to oval cells corresponding with Pautrier microabscesses and evidence of spongiosis.^14,15 The first descriptive study of RCM in the diagnosis of MF failed to identify features of tumor-stage MF that would distinguish it from patch- or plaque-stage disease. The investigators also stated that deep nodular collections of atypical lymphocytes seen on histopathology in tumor-stage MF were missed on RCM evaluation.¹⁴ Furthermore, the second descriptive study of RCM and MF, which included 2 patients with tumor-stage disease, also failed to differentiate tumor-stage MF from the patch or plaque stages.¹⁵

Because of these 2 descriptive studies, a pilot study was conducted to determine the applicability and reproducibility of RCM findings for MF diagnosis.¹⁶ Two blinded confocalists were asked to diagnose RCM images as MF when compared to either normal skin or a variety of lymphoproliferative disorders. Of 15 patients, the confocalists correctly diagnosed MF in 84% and 90% of cases, respectively. Additionally, they reported the specificity and sensitivity of the following RCM features in the diagnosis of MF: spongiosis, 88.9% and 94.7%; loss of demarcation, 88.9% and 94.7%; disarray of the epidermis, 77.8% and 89.5%; hyporefractile rings, 88.9% and 78.9%; junctional atypical lymphocytes, 100% and 73.7%; and vesiclelike structures (Pautrier microabscesses), 100% and 73.7%. Importantly, this study did not evaluate the specificity and sensitivity of MF diagnosis compared to other eczematous or inflammatory conditions that may share similar RCM findings; therefore, these results are not generalizable, and many of the RCM findings characteristically seen in MF are not specific to its diagnosis.¹⁶

One study assessed the diagnostic accuracy of RCM in evaluating erythematosquamous diseases including MF, psoriasis, contact dermatitis, discoid lupus, and subacute cutaneous lupus.¹⁷ In this study, 3 blinded confocalists achieved a 95.41% and 92.89% specificity and 89.13% and 63.33% sensitivity for psoriasis and MF, respectively. Typical features of psoriasis on RCM included parakeratosis, reduction or absence of the granular layer, papillomatosis, acanthosis with normal honeycomb pattern of the epidermis, and dilated vessels in the upper dermis. Features that were more specific to MF included epidermotropic atypical lymphocytes, interface dermatitis, pleomorphic tumor cells, and dendritic cells.¹⁷ However, atypical lymphocytes and interface dermatitis also may be seen in cutaneous lupus; therefore, additional studies are still needed to validate RCM’s utility in differentiating between erythematosquamous skin diseases, including psoriasis, cutaneous lupus, and MF. Currently, RCM findings must be interpreted in conjunction with the clinical and histologic picture.

Importantly, RCM also is limited when evaluating MF due to its limited depth of visualization, as it allows imaging only to the superficial papillary dermis. Furthermore, any infiltrative process such as epidermal hyperplasia, spongiosis, or scaling, which can be seen in MF, may further impair the imaging quality of the deeper dermis.

Conclusion

Despite its limitations, RCM has the potential to be advantageous in evaluating skin lesions suspicious for MF in real time and is a promising technology for a quick noninvasive bedside adjunct tool. Its utility in selecting the optimal site for biopsy for better yield of histopathologic results in suspected MF cases has been demonstrated.¹⁶ However, large-scale studies still are needed to evaluate RCM in the diagnosis of the wide diversity of MF lesions as well as its efficacy in selecting optimal biopsy sites.

ABSTRACT

The traditional technique for patella fracture fixation utilizes prominent hardware. Prominent hardware use, however, results in a high rate of reoperation for symptomatic implant removal. This biomechanical study evaluates the effectiveness of a novel patella fixation technique that minimizes implant prominence.

Patellar transverse osteotomies were created in 13 pairs of cadaveric knees. Paired knees were assigned to either standard fixation (SF) using cannulated partially threaded screws and stainless steel wire tension band, or buried fixation (BF) using headless compression screws with a No. 2 FiberWire tension band and a No. 5 FiberWire cerclage suture. Quadriceps tendons were cyclically loaded to full extension followed by load to failure. The gap across the fracture site, stiffness, and load to failure were measured.

The differences in stiffness and load to failure between the 2 groups were not statistically significant. During cyclic loading, significantly greater gapping was observed across the fracture site in the BF group compared with SF group (P < .05).

Both constructs failed under loads that exceeded typical loads experienced during the postoperative rehabilitation period. Nevertheless, the BF technique demonstrated larger gap formation and a reduced load to failure than the SF technique. Further clinical studies are therefore underway to determine whether the use of constructs with decreased stability but increased patient comfort could improve clinical outcomes and reduce reoperation rates.

Continue to: Patella fractures are common...

Patella fractures are common injuries that can cause considerable disability to the knee extensor apparatus.^1-3 Transverse patella fractures are the most common fracture pattern associated with patella fractures.{Harrell, 2003 #3}² Given that the patella plays a crucial role in knee extensor biomechanics, its proper integrity is vital for physiological knee motion and ambulation.⁴ Traditionally, patella fractures with >2 mm of displacement have been managed with cannulated screws or Kirschner wires (K-wires) and a stainless-steel wire tension band.^5-9 The goal in the treatment of patellar fractures is to reduce fracture fragments accurately and to minimize additional insults to the articular cartilage.¹⁰

Despite advances in surgical protocols and acceptable radiographic outcomes, functional impairment remains common after the treatment of patella fractures. Functional impairment includes knee pain, screw head pain, implant removal, wire breakage, and patella baja.¹ The need for implant removal is one of the most common complications following the open reduction internal fixation of patella fractures.^2,11 The subcutaneous and exposed nature of the patella in conjunction with soft tissue irritation resulting from standard fixation (SF) predisposes the patient toward prominence and discomfort with the retained implant. Although nonunion rates are low, the rate of implant removal can reach as high as 52%.^2,10-12 To overcome some of these complications, we designed a novel buried fixation (BF) method for the treatment of transverse fractures. Our method minimizes the amount of exposed implant to improve patient comfort and potentially reduce the need for future implant removal. These effects are achieved by using headless compression screws and nonabsorbable sutures to attenuate the soft tissue irritation associated with traditional fixation.¹³ While our novel technique has demonstrated improved clinical results, it has not been tested biomechanically against a traditional fixation technique. Therefore, this study aims to evaluate and compare the structural integrity of our novel BF technique with that of the standard technique that uses cannulated screws and wire tension band. We hypothesized that the stability provided by our technique would be similar to that provided by SF for transverse patella fractures.

MATERIALS AND METHODS

SPECIMEN PREPARATION

Thirteen matched pairs of fresh-frozen human cadaveric knees were obtained from a Cedars-Sinai approved tissue bank. Specimens were cut midfemur and were intact to the foot. Legs with major structural bony or ligamentous abnormalities, extensor mechanism disruption, or septic knees were excluded from testing. To assess the bone quality of each specimen prior to testing, dual-energy X-ray absorptiometry was performed using a GE Lunar iDXA scanner (GE Healthcare). Specimens were stored at −30°C and thawed at room temperature for 24 hours prior to biomechanical testing.

A midline anterior approach to the patella was performed, and the extensor retinaculum, quadriceps tendon, and patellar tendon were exposed. A digital caliper was used to measure the craniocaudal and mediolateral dimensions of the patella, and a transverse osteotomy (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association [AO/OTA] type 34-C1) was created at the midway point between superior and inferior poles by using an oscillating saw. The retinaculum was then incised to the level of the midaxial line of the femur. One leg from each matched pair was allocated to the SF group, and the other was allocated to the BF group. Left and right legs were alternately assigned to each group to ensure that laterality was balanced between the 2 groups.

SURGICAL TECHNIQUE

The repair of the specimens in the SF group involved the use of 2 parallel 4.0-mm partially threaded cannulated screws (Acumed) and an 18-gauge monofilament steel wire (Ethicon) in a figure-eight tension band (Figure 1A). The repair of the specimens in the BF group involved the use of 2 parallel standard Acutrak headless compression screws (Acumed), a No. 2 FiberWire (Arthrex) in a figure-eight tension band, and a No. 5 FiberWire (Arthrex) was applied as cerclage around the patella (Figure 1B).

Continue to: Mechanical testing...

MECHANICAL TESTING

Mechanical testing was performed on a biaxial 370.02 Bionix Testing System (MTS Systems Corp.). The femur was rigidly and horizontally secured to a custom-built test frame, and the lower leg was left free to move. The quadriceps tendon was secured in a freeze clamp and was attached to the MTS actuator for loading via a pulley system such that raising the actuator was translated into a simulated quadriceps extensor force.

A differential variable reluctance transducer (DVRT) (Lord MicroStrain) was placed across the osteotomy site to measure the distraction, or gap, across the fracture line. The minimum load to full extension for each specimen was then determined under a slow, controlled increase in load until the leg was in a fully extended position. Any distraction across the fracture line during the initial loading phase was determined by using digital calipers. The specimen was then subjected to a preconditioning phase with 10 cycles from 0 N to full extension under the previously determined load, which was applied at the rate of 5 N/s. Meanwhile, displacement across the fracture site was recorded via the DVRT. Following the preconditioning phase, each specimen was then tested to failure in displacement control at the rate of 1.5 mm/s. Failure was defined as implant failure (screw pullout) or DVRT gapping across the osteotomy site >3 mm.^10,14

Outcome measures included stiffness (N/mm), which was calculated as the slope of the linear change in load from full extension to failure vs DVRT displacement during the final loading phase; failure load (N); gapping (mm) across the osteotomy site at each cycle during the preconditioning phase; and failure mode (pullout vs >3.0 mm gap).

STATISTICAL ANALYSIS

An a priori power analysis revealed that 13 knees per group would be required to obtain an α of 0.05 and a power of 0.80. This calculation was based on a 20% difference in fracture displacement calculated by using the standard deviation and mean previously reported for cannulated screws with nonabsorbable sutures.¹⁴

Means and standard deviations for all dependent outcome measures were computed and compared across the independent measure of fixation type (BF vs SF) through repeated measures Analysis of variance (ANOVA-GLM, SAS 9.3, SAS Institute, Inc.) after controlling for bone mineral density (BMD), gender, and age. Multivariate repeated-measures ANOVA with Tukey's studentized range was applied to cyclic gap data. The mode of failure was compared across fixation type (BF vs SF) for matched data using McNemar’s test. Intracorrelations were computed and examined over all data and separately on the basis of screw fixation type (BF vs SF). All tests were considered statistically significant when P < .05.

Continue to: Results...

RESULTS

Specimen donors were 46% (6/13) male with an average age of 78.5 years (±13.77; range, 56-91 years) and 54% (7/13) female with an average age of 76.57 years (±14.37; range, 59-102 years). Average BMD was significantly lower in female (0.71 ± 0.18) than in male specimens (1.15 ± 0.33) (P < .05).

The average load to full extension across all specimens was 272 N (±54; range, 160-360 N) and was well balanced across matched pairs (270 ± 56 N for BF and 273 ± 54 N for SF). Of the 13 BF specimens, 4 experienced distraction across the fracture line during the determination of the minimum load to full extension. This initial pretest gap was measured with digital calipers (average, 1.5 mm; range, 0.90-1.85 mm) and added as an offset to the respective DVRT displacement data recorded during testing.

The total number of specimens included in the displacement data calculations decreased from 13 to 11 per group because DVRT data were not recorded during cyclic loading for 1 specimen and were considered unreliable in another. The maximum displacement measured across the fracture site during cyclic loading was significantly higher in the BF (0.94 ± 1.21) group than in the SF group (0.19 ± 0.26) as shown in the Table. The average slope of the gap per cycle for each specimen was calculated and compared between the BF and SF groups. The BF group demonstrated a significantly greater increase in gap per cycle than the SF group (Figure 2). Stiffness during load to failure was calculated for all but 1 specimen that did not display any measurable displacement during the final loading cycle. The average final stiffness and failure load between the BF and SF groups were not significantly different (Table). An equal number of specimens in both groups failed through gapping (6/13) and pullout (7/13).

Table. Means and Standard Deviations of the Main Outcome Measures

^aIndicates statistical significance (P < .05).

Abbreviation: NS, not significant.

Failure load was significantly positively correlated with BMD (R = 0.62, P < .001) when all specimens were grouped together. When analyzed separately, the SF group was significantly correlated with BMD (P < .01), whereas the BF group had a marginally significant correlation (P = .06) with BMD (Figure 3). In both groups, BMD was positively correlated with stiffness and negatively correlated with gapping. Neither of these trends, however, was significant.

Continue to: Discussion...

DISCUSSION

We proposed a novel BF technique for the treatment of noncomminuted transverse patella fractures. Our technique utilizes headless cannulated compression screws and nonabsorbable suture tension bands. We then biomechanically compared our proposed technique with an established fixation technique that uses partially threaded cannulated screws and stainless steel wire tension bands. We hypothesized that the mechanical response of the BF technique to cyclic and failure loading would be similar to that of the SF technique. Our results demonstrate a significant increase in gap formation across the fracture site among knees and an overall reduced load to failure in the BF group (Figure 2). Whether these inferior results manifest clinically is not yet established. Both constructs could withstand forces that are typically experienced during the postoperative period. Given the high rate of symptomatic implant removal associated with the traditional technique, the low-profile buried technique might be an attractive alternative that provides increased patient comfort but may require an extended period of postoperative protection against bony ingrowths.

Patellar fixation constructs that use a combination of cannulated screws and a wire tension band provide the best resistance to patella fracture displacement when compared with screws or wires alone.^4,15 Although this combination is biomechanically favorable, the steel wire often causes the painful irritation of the surrounding soft tissues and can break or migrate, thus increasing the rates of implant removal surgery to as high as 52%.^4,10,12,15 We developed our novel BF technique, which uses headless compression screws and a No. 2 FiberWire tension band, to address the high rates of reoperation and patient dissatisfaction associated with the SF technique.

Headless compression screws have been successfully used in the reduction and fixation of scaphoid fractures and sesamoid fractures.^16,17 The pull-out strengths of these screws are comparable with those of other commonly used screws, such as Twinfix and Herbert-Whipple screws.¹⁶ Similarly, the strength of a No. 5 FiberWire is comparable with that of an 18-gauge stainless-steel wire.^14,18 Several studies have also obtained good outcomes with nonmetallic constructs that use nonabsorbable sutures alone.^19,20 In this study, we utilized a No. 2 FiberWire as the tension band. The use of the No. 2 FiberWire facilitated threading through headless cannulated screws and created a low-profile knot. However, the use of thin FiberWire, despite a No. 5 FiberWire cerclage, likely contributed to the increase in distraction across the fracture.

The highest patellofemoral joint reaction force during level walking is approximately 35 kg (half body weight), which is equivalent to 350 N.^15,21,22 This force is similar to the average cyclic load used in this experiment (272 ± 54 N). Gapping increased in the BF group but did not reach the defined failure value of 3 mm, and the ultimate load to failure was relatively high across both groups (SF, 1123 N; BF, 973 N). These results suggest that both fixation methods can withstand the typical patellofemoral joint forces that are experienced during the postoperative period.⁴ In addition, in a clinical setting, patients are placed in hinged knee braces for at least 2 weeks to limit their flexion angle and to allow for healing and bony ingrowth. Postoperative knee-brace protection presumably increases the overall strength of the fixation.

The number of specimens (n = 26) evaluated in this study was greater than that used in other biomechanical patella fracture studies.¹⁴ Furthermore, none of our specimens were reused. Our study design was further strengthened given that fellowship-trained trauma surgeons performed all surgical procedures. Finally, the data collection and analysis of numerous clinically relevant factors, such as BMD, age, and cyclical loading, contributed to the comprehensive description of each technique with respect to patient-specific criteria.

Similar to all cadaveric studies, our data only represent the immediate postoperative condition and does not represent any healing that would occur during postoperative rehabilitation. Postoperative knee-brace protection and bone healing across the fracture site would likely strengthen both constructs in a clinical setting. In addition, the average age of our specimens is 77.5 years, and therefore does not best represent the age range (20-50 years) of the typical adult population affected by patella fractures.^3,23,24 Finally, postsurgical reduction was confirmed through visual inspection and not through fluoroscopy as in a clinical setting. Radiographic images were obtained after each experiment only to confirm screw placement post facto (Figures 4A, 4B).

CONCLUSION

This study demonstrates the utility of a novel BF technique. Nevertheless, the proposed technique exhibited increased gapping and a lower load to failure than the current gold standard. The significance of these inferior results in clinical and functional settings has not been established. The proposed BF technique may be an appealing alternative to the SF technique given its low profile and potential to reduce the rates of future implant removal. Further studies on the long-term outcomes of patients treated through the BF technique are currently under way and will ultimately determine the utility of the proposed construct.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

The traditional technique for patella fracture fixation utilizes prominent hardware. Prominent hardware use, however, results in a high rate of reoperation for symptomatic implant removal. This biomechanical study evaluates the effectiveness of a novel patella fixation technique that minimizes implant prominence.

Patellar transverse osteotomies were created in 13 pairs of cadaveric knees. Paired knees were assigned to either standard fixation (SF) using cannulated partially threaded screws and stainless steel wire tension band, or buried fixation (BF) using headless compression screws with a No. 2 FiberWire tension band and a No. 5 FiberWire cerclage suture. Quadriceps tendons were cyclically loaded to full extension followed by load to failure. The gap across the fracture site, stiffness, and load to failure were measured.

The differences in stiffness and load to failure between the 2 groups were not statistically significant. During cyclic loading, significantly greater gapping was observed across the fracture site in the BF group compared with SF group (P < .05).

Both constructs failed under loads that exceeded typical loads experienced during the postoperative rehabilitation period. Nevertheless, the BF technique demonstrated larger gap formation and a reduced load to failure than the SF technique. Further clinical studies are therefore underway to determine whether the use of constructs with decreased stability but increased patient comfort could improve clinical outcomes and reduce reoperation rates.

Continue to: Patella fractures are common...

Patella fractures are common injuries that can cause considerable disability to the knee extensor apparatus.^1-3 Transverse patella fractures are the most common fracture pattern associated with patella fractures.{Harrell, 2003 #3}² Given that the patella plays a crucial role in knee extensor biomechanics, its proper integrity is vital for physiological knee motion and ambulation.⁴ Traditionally, patella fractures with >2 mm of displacement have been managed with cannulated screws or Kirschner wires (K-wires) and a stainless-steel wire tension band.^5-9 The goal in the treatment of patellar fractures is to reduce fracture fragments accurately and to minimize additional insults to the articular cartilage.¹⁰

Despite advances in surgical protocols and acceptable radiographic outcomes, functional impairment remains common after the treatment of patella fractures. Functional impairment includes knee pain, screw head pain, implant removal, wire breakage, and patella baja.¹ The need for implant removal is one of the most common complications following the open reduction internal fixation of patella fractures.^2,11 The subcutaneous and exposed nature of the patella in conjunction with soft tissue irritation resulting from standard fixation (SF) predisposes the patient toward prominence and discomfort with the retained implant. Although nonunion rates are low, the rate of implant removal can reach as high as 52%.^2,10-12 To overcome some of these complications, we designed a novel buried fixation (BF) method for the treatment of transverse fractures. Our method minimizes the amount of exposed implant to improve patient comfort and potentially reduce the need for future implant removal. These effects are achieved by using headless compression screws and nonabsorbable sutures to attenuate the soft tissue irritation associated with traditional fixation.¹³ While our novel technique has demonstrated improved clinical results, it has not been tested biomechanically against a traditional fixation technique. Therefore, this study aims to evaluate and compare the structural integrity of our novel BF technique with that of the standard technique that uses cannulated screws and wire tension band. We hypothesized that the stability provided by our technique would be similar to that provided by SF for transverse patella fractures.

MATERIALS AND METHODS

SPECIMEN PREPARATION

Thirteen matched pairs of fresh-frozen human cadaveric knees were obtained from a Cedars-Sinai approved tissue bank. Specimens were cut midfemur and were intact to the foot. Legs with major structural bony or ligamentous abnormalities, extensor mechanism disruption, or septic knees were excluded from testing. To assess the bone quality of each specimen prior to testing, dual-energy X-ray absorptiometry was performed using a GE Lunar iDXA scanner (GE Healthcare). Specimens were stored at −30°C and thawed at room temperature for 24 hours prior to biomechanical testing.

A midline anterior approach to the patella was performed, and the extensor retinaculum, quadriceps tendon, and patellar tendon were exposed. A digital caliper was used to measure the craniocaudal and mediolateral dimensions of the patella, and a transverse osteotomy (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association [AO/OTA] type 34-C1) was created at the midway point between superior and inferior poles by using an oscillating saw. The retinaculum was then incised to the level of the midaxial line of the femur. One leg from each matched pair was allocated to the SF group, and the other was allocated to the BF group. Left and right legs were alternately assigned to each group to ensure that laterality was balanced between the 2 groups.

SURGICAL TECHNIQUE

The repair of the specimens in the SF group involved the use of 2 parallel 4.0-mm partially threaded cannulated screws (Acumed) and an 18-gauge monofilament steel wire (Ethicon) in a figure-eight tension band (Figure 1A). The repair of the specimens in the BF group involved the use of 2 parallel standard Acutrak headless compression screws (Acumed), a No. 2 FiberWire (Arthrex) in a figure-eight tension band, and a No. 5 FiberWire (Arthrex) was applied as cerclage around the patella (Figure 1B).

Continue to: Mechanical testing...

MECHANICAL TESTING

Mechanical testing was performed on a biaxial 370.02 Bionix Testing System (MTS Systems Corp.). The femur was rigidly and horizontally secured to a custom-built test frame, and the lower leg was left free to move. The quadriceps tendon was secured in a freeze clamp and was attached to the MTS actuator for loading via a pulley system such that raising the actuator was translated into a simulated quadriceps extensor force.

A differential variable reluctance transducer (DVRT) (Lord MicroStrain) was placed across the osteotomy site to measure the distraction, or gap, across the fracture line. The minimum load to full extension for each specimen was then determined under a slow, controlled increase in load until the leg was in a fully extended position. Any distraction across the fracture line during the initial loading phase was determined by using digital calipers. The specimen was then subjected to a preconditioning phase with 10 cycles from 0 N to full extension under the previously determined load, which was applied at the rate of 5 N/s. Meanwhile, displacement across the fracture site was recorded via the DVRT. Following the preconditioning phase, each specimen was then tested to failure in displacement control at the rate of 1.5 mm/s. Failure was defined as implant failure (screw pullout) or DVRT gapping across the osteotomy site >3 mm.^10,14

Outcome measures included stiffness (N/mm), which was calculated as the slope of the linear change in load from full extension to failure vs DVRT displacement during the final loading phase; failure load (N); gapping (mm) across the osteotomy site at each cycle during the preconditioning phase; and failure mode (pullout vs >3.0 mm gap).

STATISTICAL ANALYSIS

An a priori power analysis revealed that 13 knees per group would be required to obtain an α of 0.05 and a power of 0.80. This calculation was based on a 20% difference in fracture displacement calculated by using the standard deviation and mean previously reported for cannulated screws with nonabsorbable sutures.¹⁴

Means and standard deviations for all dependent outcome measures were computed and compared across the independent measure of fixation type (BF vs SF) through repeated measures Analysis of variance (ANOVA-GLM, SAS 9.3, SAS Institute, Inc.) after controlling for bone mineral density (BMD), gender, and age. Multivariate repeated-measures ANOVA with Tukey's studentized range was applied to cyclic gap data. The mode of failure was compared across fixation type (BF vs SF) for matched data using McNemar’s test. Intracorrelations were computed and examined over all data and separately on the basis of screw fixation type (BF vs SF). All tests were considered statistically significant when P < .05.

Continue to: Results...

RESULTS

Specimen donors were 46% (6/13) male with an average age of 78.5 years (±13.77; range, 56-91 years) and 54% (7/13) female with an average age of 76.57 years (±14.37; range, 59-102 years). Average BMD was significantly lower in female (0.71 ± 0.18) than in male specimens (1.15 ± 0.33) (P < .05).

The average load to full extension across all specimens was 272 N (±54; range, 160-360 N) and was well balanced across matched pairs (270 ± 56 N for BF and 273 ± 54 N for SF). Of the 13 BF specimens, 4 experienced distraction across the fracture line during the determination of the minimum load to full extension. This initial pretest gap was measured with digital calipers (average, 1.5 mm; range, 0.90-1.85 mm) and added as an offset to the respective DVRT displacement data recorded during testing.

The total number of specimens included in the displacement data calculations decreased from 13 to 11 per group because DVRT data were not recorded during cyclic loading for 1 specimen and were considered unreliable in another. The maximum displacement measured across the fracture site during cyclic loading was significantly higher in the BF (0.94 ± 1.21) group than in the SF group (0.19 ± 0.26) as shown in the Table. The average slope of the gap per cycle for each specimen was calculated and compared between the BF and SF groups. The BF group demonstrated a significantly greater increase in gap per cycle than the SF group (Figure 2). Stiffness during load to failure was calculated for all but 1 specimen that did not display any measurable displacement during the final loading cycle. The average final stiffness and failure load between the BF and SF groups were not significantly different (Table). An equal number of specimens in both groups failed through gapping (6/13) and pullout (7/13).

Table. Means and Standard Deviations of the Main Outcome Measures

^aIndicates statistical significance (P < .05).

Abbreviation: NS, not significant.

Failure load was significantly positively correlated with BMD (R = 0.62, P < .001) when all specimens were grouped together. When analyzed separately, the SF group was significantly correlated with BMD (P < .01), whereas the BF group had a marginally significant correlation (P = .06) with BMD (Figure 3). In both groups, BMD was positively correlated with stiffness and negatively correlated with gapping. Neither of these trends, however, was significant.

Continue to: Discussion...

DISCUSSION

We proposed a novel BF technique for the treatment of noncomminuted transverse patella fractures. Our technique utilizes headless cannulated compression screws and nonabsorbable suture tension bands. We then biomechanically compared our proposed technique with an established fixation technique that uses partially threaded cannulated screws and stainless steel wire tension bands. We hypothesized that the mechanical response of the BF technique to cyclic and failure loading would be similar to that of the SF technique. Our results demonstrate a significant increase in gap formation across the fracture site among knees and an overall reduced load to failure in the BF group (Figure 2). Whether these inferior results manifest clinically is not yet established. Both constructs could withstand forces that are typically experienced during the postoperative period. Given the high rate of symptomatic implant removal associated with the traditional technique, the low-profile buried technique might be an attractive alternative that provides increased patient comfort but may require an extended period of postoperative protection against bony ingrowths.

Patellar fixation constructs that use a combination of cannulated screws and a wire tension band provide the best resistance to patella fracture displacement when compared with screws or wires alone.^4,15 Although this combination is biomechanically favorable, the steel wire often causes the painful irritation of the surrounding soft tissues and can break or migrate, thus increasing the rates of implant removal surgery to as high as 52%.^4,10,12,15 We developed our novel BF technique, which uses headless compression screws and a No. 2 FiberWire tension band, to address the high rates of reoperation and patient dissatisfaction associated with the SF technique.

Headless compression screws have been successfully used in the reduction and fixation of scaphoid fractures and sesamoid fractures.^16,17 The pull-out strengths of these screws are comparable with those of other commonly used screws, such as Twinfix and Herbert-Whipple screws.¹⁶ Similarly, the strength of a No. 5 FiberWire is comparable with that of an 18-gauge stainless-steel wire.^14,18 Several studies have also obtained good outcomes with nonmetallic constructs that use nonabsorbable sutures alone.^19,20 In this study, we utilized a No. 2 FiberWire as the tension band. The use of the No. 2 FiberWire facilitated threading through headless cannulated screws and created a low-profile knot. However, the use of thin FiberWire, despite a No. 5 FiberWire cerclage, likely contributed to the increase in distraction across the fracture.

The highest patellofemoral joint reaction force during level walking is approximately 35 kg (half body weight), which is equivalent to 350 N.^15,21,22 This force is similar to the average cyclic load used in this experiment (272 ± 54 N). Gapping increased in the BF group but did not reach the defined failure value of 3 mm, and the ultimate load to failure was relatively high across both groups (SF, 1123 N; BF, 973 N). These results suggest that both fixation methods can withstand the typical patellofemoral joint forces that are experienced during the postoperative period.⁴ In addition, in a clinical setting, patients are placed in hinged knee braces for at least 2 weeks to limit their flexion angle and to allow for healing and bony ingrowth. Postoperative knee-brace protection presumably increases the overall strength of the fixation.

The number of specimens (n = 26) evaluated in this study was greater than that used in other biomechanical patella fracture studies.¹⁴ Furthermore, none of our specimens were reused. Our study design was further strengthened given that fellowship-trained trauma surgeons performed all surgical procedures. Finally, the data collection and analysis of numerous clinically relevant factors, such as BMD, age, and cyclical loading, contributed to the comprehensive description of each technique with respect to patient-specific criteria.

Similar to all cadaveric studies, our data only represent the immediate postoperative condition and does not represent any healing that would occur during postoperative rehabilitation. Postoperative knee-brace protection and bone healing across the fracture site would likely strengthen both constructs in a clinical setting. In addition, the average age of our specimens is 77.5 years, and therefore does not best represent the age range (20-50 years) of the typical adult population affected by patella fractures.^3,23,24 Finally, postsurgical reduction was confirmed through visual inspection and not through fluoroscopy as in a clinical setting. Radiographic images were obtained after each experiment only to confirm screw placement post facto (Figures 4A, 4B).

CONCLUSION

This study demonstrates the utility of a novel BF technique. Nevertheless, the proposed technique exhibited increased gapping and a lower load to failure than the current gold standard. The significance of these inferior results in clinical and functional settings has not been established. The proposed BF technique may be an appealing alternative to the SF technique given its low profile and potential to reduce the rates of future implant removal. Further studies on the long-term outcomes of patients treated through the BF technique are currently under way and will ultimately determine the utility of the proposed construct.

This paper will be judged for the Resident Writer’s Award.

ABSTRACT

The traditional technique for patella fracture fixation utilizes prominent hardware. Prominent hardware use, however, results in a high rate of reoperation for symptomatic implant removal. This biomechanical study evaluates the effectiveness of a novel patella fixation technique that minimizes implant prominence.

Patellar transverse osteotomies were created in 13 pairs of cadaveric knees. Paired knees were assigned to either standard fixation (SF) using cannulated partially threaded screws and stainless steel wire tension band, or buried fixation (BF) using headless compression screws with a No. 2 FiberWire tension band and a No. 5 FiberWire cerclage suture. Quadriceps tendons were cyclically loaded to full extension followed by load to failure. The gap across the fracture site, stiffness, and load to failure were measured.

The differences in stiffness and load to failure between the 2 groups were not statistically significant. During cyclic loading, significantly greater gapping was observed across the fracture site in the BF group compared with SF group (P < .05).

Both constructs failed under loads that exceeded typical loads experienced during the postoperative rehabilitation period. Nevertheless, the BF technique demonstrated larger gap formation and a reduced load to failure than the SF technique. Further clinical studies are therefore underway to determine whether the use of constructs with decreased stability but increased patient comfort could improve clinical outcomes and reduce reoperation rates.

Continue to: Patella fractures are common...

Patella fractures are common injuries that can cause considerable disability to the knee extensor apparatus.^1-3 Transverse patella fractures are the most common fracture pattern associated with patella fractures.{Harrell, 2003 #3}² Given that the patella plays a crucial role in knee extensor biomechanics, its proper integrity is vital for physiological knee motion and ambulation.⁴ Traditionally, patella fractures with >2 mm of displacement have been managed with cannulated screws or Kirschner wires (K-wires) and a stainless-steel wire tension band.^5-9 The goal in the treatment of patellar fractures is to reduce fracture fragments accurately and to minimize additional insults to the articular cartilage.¹⁰

Despite advances in surgical protocols and acceptable radiographic outcomes, functional impairment remains common after the treatment of patella fractures. Functional impairment includes knee pain, screw head pain, implant removal, wire breakage, and patella baja.¹ The need for implant removal is one of the most common complications following the open reduction internal fixation of patella fractures.^2,11 The subcutaneous and exposed nature of the patella in conjunction with soft tissue irritation resulting from standard fixation (SF) predisposes the patient toward prominence and discomfort with the retained implant. Although nonunion rates are low, the rate of implant removal can reach as high as 52%.^2,10-12 To overcome some of these complications, we designed a novel buried fixation (BF) method for the treatment of transverse fractures. Our method minimizes the amount of exposed implant to improve patient comfort and potentially reduce the need for future implant removal. These effects are achieved by using headless compression screws and nonabsorbable sutures to attenuate the soft tissue irritation associated with traditional fixation.¹³ While our novel technique has demonstrated improved clinical results, it has not been tested biomechanically against a traditional fixation technique. Therefore, this study aims to evaluate and compare the structural integrity of our novel BF technique with that of the standard technique that uses cannulated screws and wire tension band. We hypothesized that the stability provided by our technique would be similar to that provided by SF for transverse patella fractures.

MATERIALS AND METHODS

SPECIMEN PREPARATION

Thirteen matched pairs of fresh-frozen human cadaveric knees were obtained from a Cedars-Sinai approved tissue bank. Specimens were cut midfemur and were intact to the foot. Legs with major structural bony or ligamentous abnormalities, extensor mechanism disruption, or septic knees were excluded from testing. To assess the bone quality of each specimen prior to testing, dual-energy X-ray absorptiometry was performed using a GE Lunar iDXA scanner (GE Healthcare). Specimens were stored at −30°C and thawed at room temperature for 24 hours prior to biomechanical testing.

A midline anterior approach to the patella was performed, and the extensor retinaculum, quadriceps tendon, and patellar tendon were exposed. A digital caliper was used to measure the craniocaudal and mediolateral dimensions of the patella, and a transverse osteotomy (Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association [AO/OTA] type 34-C1) was created at the midway point between superior and inferior poles by using an oscillating saw. The retinaculum was then incised to the level of the midaxial line of the femur. One leg from each matched pair was allocated to the SF group, and the other was allocated to the BF group. Left and right legs were alternately assigned to each group to ensure that laterality was balanced between the 2 groups.

SURGICAL TECHNIQUE

The repair of the specimens in the SF group involved the use of 2 parallel 4.0-mm partially threaded cannulated screws (Acumed) and an 18-gauge monofilament steel wire (Ethicon) in a figure-eight tension band (Figure 1A). The repair of the specimens in the BF group involved the use of 2 parallel standard Acutrak headless compression screws (Acumed), a No. 2 FiberWire (Arthrex) in a figure-eight tension band, and a No. 5 FiberWire (Arthrex) was applied as cerclage around the patella (Figure 1B).

Continue to: Mechanical testing...

MECHANICAL TESTING

Mechanical testing was performed on a biaxial 370.02 Bionix Testing System (MTS Systems Corp.). The femur was rigidly and horizontally secured to a custom-built test frame, and the lower leg was left free to move. The quadriceps tendon was secured in a freeze clamp and was attached to the MTS actuator for loading via a pulley system such that raising the actuator was translated into a simulated quadriceps extensor force.

A differential variable reluctance transducer (DVRT) (Lord MicroStrain) was placed across the osteotomy site to measure the distraction, or gap, across the fracture line. The minimum load to full extension for each specimen was then determined under a slow, controlled increase in load until the leg was in a fully extended position. Any distraction across the fracture line during the initial loading phase was determined by using digital calipers. The specimen was then subjected to a preconditioning phase with 10 cycles from 0 N to full extension under the previously determined load, which was applied at the rate of 5 N/s. Meanwhile, displacement across the fracture site was recorded via the DVRT. Following the preconditioning phase, each specimen was then tested to failure in displacement control at the rate of 1.5 mm/s. Failure was defined as implant failure (screw pullout) or DVRT gapping across the osteotomy site >3 mm.^10,14

Outcome measures included stiffness (N/mm), which was calculated as the slope of the linear change in load from full extension to failure vs DVRT displacement during the final loading phase; failure load (N); gapping (mm) across the osteotomy site at each cycle during the preconditioning phase; and failure mode (pullout vs >3.0 mm gap).

STATISTICAL ANALYSIS

An a priori power analysis revealed that 13 knees per group would be required to obtain an α of 0.05 and a power of 0.80. This calculation was based on a 20% difference in fracture displacement calculated by using the standard deviation and mean previously reported for cannulated screws with nonabsorbable sutures.¹⁴

Means and standard deviations for all dependent outcome measures were computed and compared across the independent measure of fixation type (BF vs SF) through repeated measures Analysis of variance (ANOVA-GLM, SAS 9.3, SAS Institute, Inc.) after controlling for bone mineral density (BMD), gender, and age. Multivariate repeated-measures ANOVA with Tukey's studentized range was applied to cyclic gap data. The mode of failure was compared across fixation type (BF vs SF) for matched data using McNemar’s test. Intracorrelations were computed and examined over all data and separately on the basis of screw fixation type (BF vs SF). All tests were considered statistically significant when P < .05.

Continue to: Results...

RESULTS

Specimen donors were 46% (6/13) male with an average age of 78.5 years (±13.77; range, 56-91 years) and 54% (7/13) female with an average age of 76.57 years (±14.37; range, 59-102 years). Average BMD was significantly lower in female (0.71 ± 0.18) than in male specimens (1.15 ± 0.33) (P < .05).

The average load to full extension across all specimens was 272 N (±54; range, 160-360 N) and was well balanced across matched pairs (270 ± 56 N for BF and 273 ± 54 N for SF). Of the 13 BF specimens, 4 experienced distraction across the fracture line during the determination of the minimum load to full extension. This initial pretest gap was measured with digital calipers (average, 1.5 mm; range, 0.90-1.85 mm) and added as an offset to the respective DVRT displacement data recorded during testing.

The total number of specimens included in the displacement data calculations decreased from 13 to 11 per group because DVRT data were not recorded during cyclic loading for 1 specimen and were considered unreliable in another. The maximum displacement measured across the fracture site during cyclic loading was significantly higher in the BF (0.94 ± 1.21) group than in the SF group (0.19 ± 0.26) as shown in the Table. The average slope of the gap per cycle for each specimen was calculated and compared between the BF and SF groups. The BF group demonstrated a significantly greater increase in gap per cycle than the SF group (Figure 2). Stiffness during load to failure was calculated for all but 1 specimen that did not display any measurable displacement during the final loading cycle. The average final stiffness and failure load between the BF and SF groups were not significantly different (Table). An equal number of specimens in both groups failed through gapping (6/13) and pullout (7/13).

Table. Means and Standard Deviations of the Main Outcome Measures

^aIndicates statistical significance (P < .05).

Abbreviation: NS, not significant.

Failure load was significantly positively correlated with BMD (R = 0.62, P < .001) when all specimens were grouped together. When analyzed separately, the SF group was significantly correlated with BMD (P < .01), whereas the BF group had a marginally significant correlation (P = .06) with BMD (Figure 3). In both groups, BMD was positively correlated with stiffness and negatively correlated with gapping. Neither of these trends, however, was significant.

Continue to: Discussion...

DISCUSSION

We proposed a novel BF technique for the treatment of noncomminuted transverse patella fractures. Our technique utilizes headless cannulated compression screws and nonabsorbable suture tension bands. We then biomechanically compared our proposed technique with an established fixation technique that uses partially threaded cannulated screws and stainless steel wire tension bands. We hypothesized that the mechanical response of the BF technique to cyclic and failure loading would be similar to that of the SF technique. Our results demonstrate a significant increase in gap formation across the fracture site among knees and an overall reduced load to failure in the BF group (Figure 2). Whether these inferior results manifest clinically is not yet established. Both constructs could withstand forces that are typically experienced during the postoperative period. Given the high rate of symptomatic implant removal associated with the traditional technique, the low-profile buried technique might be an attractive alternative that provides increased patient comfort but may require an extended period of postoperative protection against bony ingrowths.

Patellar fixation constructs that use a combination of cannulated screws and a wire tension band provide the best resistance to patella fracture displacement when compared with screws or wires alone.^4,15 Although this combination is biomechanically favorable, the steel wire often causes the painful irritation of the surrounding soft tissues and can break or migrate, thus increasing the rates of implant removal surgery to as high as 52%.^4,10,12,15 We developed our novel BF technique, which uses headless compression screws and a No. 2 FiberWire tension band, to address the high rates of reoperation and patient dissatisfaction associated with the SF technique.

Headless compression screws have been successfully used in the reduction and fixation of scaphoid fractures and sesamoid fractures.^16,17 The pull-out strengths of these screws are comparable with those of other commonly used screws, such as Twinfix and Herbert-Whipple screws.¹⁶ Similarly, the strength of a No. 5 FiberWire is comparable with that of an 18-gauge stainless-steel wire.^14,18 Several studies have also obtained good outcomes with nonmetallic constructs that use nonabsorbable sutures alone.^19,20 In this study, we utilized a No. 2 FiberWire as the tension band. The use of the No. 2 FiberWire facilitated threading through headless cannulated screws and created a low-profile knot. However, the use of thin FiberWire, despite a No. 5 FiberWire cerclage, likely contributed to the increase in distraction across the fracture.

The highest patellofemoral joint reaction force during level walking is approximately 35 kg (half body weight), which is equivalent to 350 N.^15,21,22 This force is similar to the average cyclic load used in this experiment (272 ± 54 N). Gapping increased in the BF group but did not reach the defined failure value of 3 mm, and the ultimate load to failure was relatively high across both groups (SF, 1123 N; BF, 973 N). These results suggest that both fixation methods can withstand the typical patellofemoral joint forces that are experienced during the postoperative period.⁴ In addition, in a clinical setting, patients are placed in hinged knee braces for at least 2 weeks to limit their flexion angle and to allow for healing and bony ingrowth. Postoperative knee-brace protection presumably increases the overall strength of the fixation.

The number of specimens (n = 26) evaluated in this study was greater than that used in other biomechanical patella fracture studies.¹⁴ Furthermore, none of our specimens were reused. Our study design was further strengthened given that fellowship-trained trauma surgeons performed all surgical procedures. Finally, the data collection and analysis of numerous clinically relevant factors, such as BMD, age, and cyclical loading, contributed to the comprehensive description of each technique with respect to patient-specific criteria.

Similar to all cadaveric studies, our data only represent the immediate postoperative condition and does not represent any healing that would occur during postoperative rehabilitation. Postoperative knee-brace protection and bone healing across the fracture site would likely strengthen both constructs in a clinical setting. In addition, the average age of our specimens is 77.5 years, and therefore does not best represent the age range (20-50 years) of the typical adult population affected by patella fractures.^3,23,24 Finally, postsurgical reduction was confirmed through visual inspection and not through fluoroscopy as in a clinical setting. Radiographic images were obtained after each experiment only to confirm screw placement post facto (Figures 4A, 4B).

CONCLUSION

This study demonstrates the utility of a novel BF technique. Nevertheless, the proposed technique exhibited increased gapping and a lower load to failure than the current gold standard. The significance of these inferior results in clinical and functional settings has not been established. The proposed BF technique may be an appealing alternative to the SF technique given its low profile and potential to reduce the rates of future implant removal. Further studies on the long-term outcomes of patients treated through the BF technique are currently under way and will ultimately determine the utility of the proposed construct.

This paper will be judged for the Resident Writer’s Award.

ORLANDO – Serum uric acid lowering might help prevent kidney disease in children with type 2 diabetes mellitus, according to a 7-year investigation of 539 children.

Every 1-mg/dL climb in baseline serum uric acid increased the risk of subsequent elevated urine albumin excretion 1.23 fold, after adjustment for potential confounders (P = .02).

The finding adds to growing evidence that serum uric acid (SUA) isn’t just a marker of diabetic kidney disease, but a contributor to it. “There is definitely” cross-talk between gout and diabetes, said lead investigator Petter Bjornstad, MD, assistant professor of pediatric endocrinology at the University of Colorado, Aurora.

Elevated SUA is common in both conditions and a risk factor for kidney disease. Newer studies have linked higher levels to nephron number decline and other pathologies, perhaps through renal inflammation. Allopurinol, the traditional uric acid lowering agent in gout, is already under investigation to prevent kidney decline in adults with type 1 diabetes mellitus. There’s also evidence that the potent uric acid lowering agent, febuxostat (Uloric), attenuates hypofiltration in early diabetic kidney disease.

M. Alexander Otto/MDedge News

[email protected]

SOURCE: Bjornstad P et al. ADA 2018, abstract 339-OR.

ORLANDO – Serum uric acid lowering might help prevent kidney disease in children with type 2 diabetes mellitus, according to a 7-year investigation of 539 children.

Every 1-mg/dL climb in baseline serum uric acid increased the risk of subsequent elevated urine albumin excretion 1.23 fold, after adjustment for potential confounders (P = .02).

The finding adds to growing evidence that serum uric acid (SUA) isn’t just a marker of diabetic kidney disease, but a contributor to it. “There is definitely” cross-talk between gout and diabetes, said lead investigator Petter Bjornstad, MD, assistant professor of pediatric endocrinology at the University of Colorado, Aurora.

Elevated SUA is common in both conditions and a risk factor for kidney disease. Newer studies have linked higher levels to nephron number decline and other pathologies, perhaps through renal inflammation. Allopurinol, the traditional uric acid lowering agent in gout, is already under investigation to prevent kidney decline in adults with type 1 diabetes mellitus. There’s also evidence that the potent uric acid lowering agent, febuxostat (Uloric), attenuates hypofiltration in early diabetic kidney disease.

M. Alexander Otto/MDedge News

[email protected]

SOURCE: Bjornstad P et al. ADA 2018, abstract 339-OR.

ORLANDO – Serum uric acid lowering might help prevent kidney disease in children with type 2 diabetes mellitus, according to a 7-year investigation of 539 children.

Every 1-mg/dL climb in baseline serum uric acid increased the risk of subsequent elevated urine albumin excretion 1.23 fold, after adjustment for potential confounders (P = .02).

The finding adds to growing evidence that serum uric acid (SUA) isn’t just a marker of diabetic kidney disease, but a contributor to it. “There is definitely” cross-talk between gout and diabetes, said lead investigator Petter Bjornstad, MD, assistant professor of pediatric endocrinology at the University of Colorado, Aurora.

Elevated SUA is common in both conditions and a risk factor for kidney disease. Newer studies have linked higher levels to nephron number decline and other pathologies, perhaps through renal inflammation. Allopurinol, the traditional uric acid lowering agent in gout, is already under investigation to prevent kidney decline in adults with type 1 diabetes mellitus. There’s also evidence that the potent uric acid lowering agent, febuxostat (Uloric), attenuates hypofiltration in early diabetic kidney disease.

M. Alexander Otto/MDedge News

[email protected]

SOURCE: Bjornstad P et al. ADA 2018, abstract 339-OR.

Vitamin D receptors are found in every cell of the body and have been shown to play a role in bone, neural, and cardiovascular health; immune regulation; and possibly cancer prevention via the regulation of cell differentiation, proliferation, and apoptosis.¹ Although it is controversial, vitamin D deficiency has been associated with various forms of nonscarring hair loss,^2-4 including telogen effluvium, androgenetic alopecia, and alopecia areata. We describe a notable case of nonscarring alopecia associated with vitamin D deficiency in which vitamin D replacement therapy promoted hair regrowth.

Case Report

An otherwise healthy 34-year-old black woman presented to the Hair and Nail Clinic at the University of Pittsburgh Medical Center (Pittsburgh, Pennsylvania) for evaluation of progressive hair loss of 4 years’ duration that began shortly after her fourth child was born. Although she denied any history of excessive shedding, she stated that she used to have shoulder-length hair and somehow it had become extremely short without shaving or cutting the hair (Figure 1). Her current medications included a progestin intrauterine device and biotin 10 mg once daily, the latter of which she had taken for several months for the hair loss without any improvement.

On physical examination, the patient was noted to have diffusely thinning, short, brittle hair. Trichoscopy was notable for hairs of varying diameters, with some fractured at the level of the follicular ostia but no yellow dots at the follicular openings or exclamation point hairs. No scarring or erythema was seen on the scalp. The patient refused several of our team’s recommendations for scalp biopsy due to needle phobia. A hair growth window was made that showed good regrowth at 2 weeks after the initial presentation. Initial blood work revealed a total serum 25-hydroxyvitamin D level of 12 ng/mL (optimal, >30 ng/mL). Complete blood cell count, hormonal panel, zinc level, iron level, and thyroid studies were all normal.

The patient was started on vitamin D₃ replacement therapy 50,000 IU once weekly for 4 weeks followed by 1000 IU once daily for 6 months. No other topical or systemic treatments were administered for the nonscarring alopecia. At a follow-up visit 6 months later, the patient’s vitamin D level was 36 ng/mL, and she had noticeable hair regrowth (Figure 2). At this time, the diagnosis of nonscarring alopecia associated with vitamin D deficiency was made.

Comment

Vitamin D is a fat-soluble vitamin that can be obtained via sun exposure, food sources (eg, fish, vitamin D–fortified foods), and direct supplementation.⁵ It has been estimated that nearly 1 billion individuals worldwide⁶ and approximately 41.6% of US adults are vitamin D deficient.⁷ Certainly not all of these individuals will present with alopecia, but in patients with hair loss, we suggest that vitamin D deficiency is an important factor to consider. Risk factors for vitamin D deficiency include older age, obesity, darker skin types, residence in northern latitudes, and malabsorption syndromes.⁷

Pathogenesis
Vitamin D is thought to play a role in the normal initiation and completion of the hair cycle as well as the differentiation of the follicular and interfollicular epidermis. The vitamin D receptor (VDR) is thought to induce the development of mature anagen hairs via the canonical WNT-β-catenin and hedgehog signaling pathways.⁸ In the absence of VDRs, the stem cells in the bulge of the hair follicle have an impaired ability to replicate, and as a result, VDR-deficient mice have shown near-total hair loss.^9-12 We propose that vitamin D deficiency can not only be a trigger for hair loss but also can perpetuate hair loss and poor regrowth.

Diagnosis and Prevention of Vitamin D Deficiency
In the skin, 7-dehydrocholesterol is converted to previtamin D₃ via UVB light, followed by subsequent conversion to vitamin D₃. Dietary sources are in the form of either vitamin D₂ or D₃, both of which are converted in the liver to 25-hydroxyvitamin D, the major circulating metabolite. In the kidneys, 25-hydroxyvitamin D is then converted to 1,25-dihydroxyvitamin D, the biologically active form. Paradoxically, serum levels of 1,25-dihydroxyvitamin D can be normal or high in the setting of vitamin D deficiency; therefore, serum total 25-hydroxyvitamin D is the best way to assess a patient’s vitamin D status.^5,13

The optimal serum 25-hydroxyvitamin D level is controversial. Recommendations range between 20 to 40 ng/mL¹⁴ and 30 to 50 ng/mL.^13,15,16 Vitamin D levels higher than 50 ng/mL have been correlated with an increased risk of bone fractures and certain cancers.^16-18 Vitamin D toxicity usually is noted in serum levels greater than 88 ng/mL; symptoms of toxicity include hypercalcemia, nausea, vomiting, and muscle weakness. For nondeficient patients, the National Academy of Medicine (formerly the Institute of Medicine) recommended an upper limit of 4000 IU daily.¹⁴ The optimal dose in preventing vitamin D deficiency ranges from 600 to 1000 IU daily.^13-15

Treatment of Vitamin D Deficiency
In the setting of vitamin D deficiency, the amount required for repletion often is dependent on each individual’s ability to absorb and convert to 25-hydroxyvitamin D. Typically every 100 IU of vitamin D correlates with a 0.7 to 1.0 ng/mL increase in serum 25-hydroxyvitamin D levels.¹⁹ There are multiple dosing regimens used to achieve the desired serum 25-hydroxyvitamin D levels in deficient patients. One recommendation from the Endocrine Society is 50,000 IU once weekly for 6 to 8 weeks (single doses >50,000 IU typically are not recommended due to increased risk for toxicity), followed by 600 to 1000 IU once daily in children and 1500 to 2000 IU once daily in adults thereafter.¹³ In patients with vitamin D deficiency, reassessment of serum 25-hydroxyvitamin D levels is recommended after 3 to 4 months of treatment, and adjustments to the repletion regimen should be made as needed.^15,16 Generally, vitamin D₃ is recommended over vitamin D₂ due to enhanced efficacy in raising serum 25-hydroxyvitamin D levels.²⁰

Vitamin D Deficiency in Alopecia
Although most recommendations are given in the interest of optimizing bone health, in the setting of alopecia, we set a similar serum 25-hydroxyvitamin D goal of greater than 30 ng/mL. We recommend treatment with vitamin D₃ and practice the following repletion protocol: 50,000 IU once weekly for 4 weeks, followed by 1000 IU once daily for at least 8 weeks for serum 25-hydroxyvitamin D levels less than 20 ng/mL. For serum hydroxyvitamin D levels between 20 and 29 ng/mL, we recommend 1000 IU once daily for at least 12 weeks. We recheck blood levels again in 3 months. If levels fail to normalize, we will refer the patient to endocrinology. If levels return to normal, we transition to a daily multivitamin with vitamin D (400–800 IU) once daily and refer the patient back to the primary care physician for long-term monitoring.

Vitamin D receptors are found in every cell of the body and have been shown to play a role in bone, neural, and cardiovascular health; immune regulation; and possibly cancer prevention via the regulation of cell differentiation, proliferation, and apoptosis.¹ Although it is controversial, vitamin D deficiency has been associated with various forms of nonscarring hair loss,^2-4 including telogen effluvium, androgenetic alopecia, and alopecia areata. We describe a notable case of nonscarring alopecia associated with vitamin D deficiency in which vitamin D replacement therapy promoted hair regrowth.

Case Report

An otherwise healthy 34-year-old black woman presented to the Hair and Nail Clinic at the University of Pittsburgh Medical Center (Pittsburgh, Pennsylvania) for evaluation of progressive hair loss of 4 years’ duration that began shortly after her fourth child was born. Although she denied any history of excessive shedding, she stated that she used to have shoulder-length hair and somehow it had become extremely short without shaving or cutting the hair (Figure 1). Her current medications included a progestin intrauterine device and biotin 10 mg once daily, the latter of which she had taken for several months for the hair loss without any improvement.

On physical examination, the patient was noted to have diffusely thinning, short, brittle hair. Trichoscopy was notable for hairs of varying diameters, with some fractured at the level of the follicular ostia but no yellow dots at the follicular openings or exclamation point hairs. No scarring or erythema was seen on the scalp. The patient refused several of our team’s recommendations for scalp biopsy due to needle phobia. A hair growth window was made that showed good regrowth at 2 weeks after the initial presentation. Initial blood work revealed a total serum 25-hydroxyvitamin D level of 12 ng/mL (optimal, >30 ng/mL). Complete blood cell count, hormonal panel, zinc level, iron level, and thyroid studies were all normal.

The patient was started on vitamin D₃ replacement therapy 50,000 IU once weekly for 4 weeks followed by 1000 IU once daily for 6 months. No other topical or systemic treatments were administered for the nonscarring alopecia. At a follow-up visit 6 months later, the patient’s vitamin D level was 36 ng/mL, and she had noticeable hair regrowth (Figure 2). At this time, the diagnosis of nonscarring alopecia associated with vitamin D deficiency was made.

Comment

Vitamin D is a fat-soluble vitamin that can be obtained via sun exposure, food sources (eg, fish, vitamin D–fortified foods), and direct supplementation.⁵ It has been estimated that nearly 1 billion individuals worldwide⁶ and approximately 41.6% of US adults are vitamin D deficient.⁷ Certainly not all of these individuals will present with alopecia, but in patients with hair loss, we suggest that vitamin D deficiency is an important factor to consider. Risk factors for vitamin D deficiency include older age, obesity, darker skin types, residence in northern latitudes, and malabsorption syndromes.⁷

Pathogenesis
Vitamin D is thought to play a role in the normal initiation and completion of the hair cycle as well as the differentiation of the follicular and interfollicular epidermis. The vitamin D receptor (VDR) is thought to induce the development of mature anagen hairs via the canonical WNT-β-catenin and hedgehog signaling pathways.⁸ In the absence of VDRs, the stem cells in the bulge of the hair follicle have an impaired ability to replicate, and as a result, VDR-deficient mice have shown near-total hair loss.^9-12 We propose that vitamin D deficiency can not only be a trigger for hair loss but also can perpetuate hair loss and poor regrowth.

Diagnosis and Prevention of Vitamin D Deficiency
In the skin, 7-dehydrocholesterol is converted to previtamin D₃ via UVB light, followed by subsequent conversion to vitamin D₃. Dietary sources are in the form of either vitamin D₂ or D₃, both of which are converted in the liver to 25-hydroxyvitamin D, the major circulating metabolite. In the kidneys, 25-hydroxyvitamin D is then converted to 1,25-dihydroxyvitamin D, the biologically active form. Paradoxically, serum levels of 1,25-dihydroxyvitamin D can be normal or high in the setting of vitamin D deficiency; therefore, serum total 25-hydroxyvitamin D is the best way to assess a patient’s vitamin D status.^5,13

The optimal serum 25-hydroxyvitamin D level is controversial. Recommendations range between 20 to 40 ng/mL¹⁴ and 30 to 50 ng/mL.^13,15,16 Vitamin D levels higher than 50 ng/mL have been correlated with an increased risk of bone fractures and certain cancers.^16-18 Vitamin D toxicity usually is noted in serum levels greater than 88 ng/mL; symptoms of toxicity include hypercalcemia, nausea, vomiting, and muscle weakness. For nondeficient patients, the National Academy of Medicine (formerly the Institute of Medicine) recommended an upper limit of 4000 IU daily.¹⁴ The optimal dose in preventing vitamin D deficiency ranges from 600 to 1000 IU daily.^13-15

Treatment of Vitamin D Deficiency
In the setting of vitamin D deficiency, the amount required for repletion often is dependent on each individual’s ability to absorb and convert to 25-hydroxyvitamin D. Typically every 100 IU of vitamin D correlates with a 0.7 to 1.0 ng/mL increase in serum 25-hydroxyvitamin D levels.¹⁹ There are multiple dosing regimens used to achieve the desired serum 25-hydroxyvitamin D levels in deficient patients. One recommendation from the Endocrine Society is 50,000 IU once weekly for 6 to 8 weeks (single doses >50,000 IU typically are not recommended due to increased risk for toxicity), followed by 600 to 1000 IU once daily in children and 1500 to 2000 IU once daily in adults thereafter.¹³ In patients with vitamin D deficiency, reassessment of serum 25-hydroxyvitamin D levels is recommended after 3 to 4 months of treatment, and adjustments to the repletion regimen should be made as needed.^15,16 Generally, vitamin D₃ is recommended over vitamin D₂ due to enhanced efficacy in raising serum 25-hydroxyvitamin D levels.²⁰

Vitamin D Deficiency in Alopecia
Although most recommendations are given in the interest of optimizing bone health, in the setting of alopecia, we set a similar serum 25-hydroxyvitamin D goal of greater than 30 ng/mL. We recommend treatment with vitamin D₃ and practice the following repletion protocol: 50,000 IU once weekly for 4 weeks, followed by 1000 IU once daily for at least 8 weeks for serum 25-hydroxyvitamin D levels less than 20 ng/mL. For serum hydroxyvitamin D levels between 20 and 29 ng/mL, we recommend 1000 IU once daily for at least 12 weeks. We recheck blood levels again in 3 months. If levels fail to normalize, we will refer the patient to endocrinology. If levels return to normal, we transition to a daily multivitamin with vitamin D (400–800 IU) once daily and refer the patient back to the primary care physician for long-term monitoring.

Vitamin D receptors are found in every cell of the body and have been shown to play a role in bone, neural, and cardiovascular health; immune regulation; and possibly cancer prevention via the regulation of cell differentiation, proliferation, and apoptosis.¹ Although it is controversial, vitamin D deficiency has been associated with various forms of nonscarring hair loss,^2-4 including telogen effluvium, androgenetic alopecia, and alopecia areata. We describe a notable case of nonscarring alopecia associated with vitamin D deficiency in which vitamin D replacement therapy promoted hair regrowth.

Case Report

An otherwise healthy 34-year-old black woman presented to the Hair and Nail Clinic at the University of Pittsburgh Medical Center (Pittsburgh, Pennsylvania) for evaluation of progressive hair loss of 4 years’ duration that began shortly after her fourth child was born. Although she denied any history of excessive shedding, she stated that she used to have shoulder-length hair and somehow it had become extremely short without shaving or cutting the hair (Figure 1). Her current medications included a progestin intrauterine device and biotin 10 mg once daily, the latter of which she had taken for several months for the hair loss without any improvement.

On physical examination, the patient was noted to have diffusely thinning, short, brittle hair. Trichoscopy was notable for hairs of varying diameters, with some fractured at the level of the follicular ostia but no yellow dots at the follicular openings or exclamation point hairs. No scarring or erythema was seen on the scalp. The patient refused several of our team’s recommendations for scalp biopsy due to needle phobia. A hair growth window was made that showed good regrowth at 2 weeks after the initial presentation. Initial blood work revealed a total serum 25-hydroxyvitamin D level of 12 ng/mL (optimal, >30 ng/mL). Complete blood cell count, hormonal panel, zinc level, iron level, and thyroid studies were all normal.

The patient was started on vitamin D₃ replacement therapy 50,000 IU once weekly for 4 weeks followed by 1000 IU once daily for 6 months. No other topical or systemic treatments were administered for the nonscarring alopecia. At a follow-up visit 6 months later, the patient’s vitamin D level was 36 ng/mL, and she had noticeable hair regrowth (Figure 2). At this time, the diagnosis of nonscarring alopecia associated with vitamin D deficiency was made.

Comment

Vitamin D is a fat-soluble vitamin that can be obtained via sun exposure, food sources (eg, fish, vitamin D–fortified foods), and direct supplementation.⁵ It has been estimated that nearly 1 billion individuals worldwide⁶ and approximately 41.6% of US adults are vitamin D deficient.⁷ Certainly not all of these individuals will present with alopecia, but in patients with hair loss, we suggest that vitamin D deficiency is an important factor to consider. Risk factors for vitamin D deficiency include older age, obesity, darker skin types, residence in northern latitudes, and malabsorption syndromes.⁷

Pathogenesis
Vitamin D is thought to play a role in the normal initiation and completion of the hair cycle as well as the differentiation of the follicular and interfollicular epidermis. The vitamin D receptor (VDR) is thought to induce the development of mature anagen hairs via the canonical WNT-β-catenin and hedgehog signaling pathways.⁸ In the absence of VDRs, the stem cells in the bulge of the hair follicle have an impaired ability to replicate, and as a result, VDR-deficient mice have shown near-total hair loss.^9-12 We propose that vitamin D deficiency can not only be a trigger for hair loss but also can perpetuate hair loss and poor regrowth.

Diagnosis and Prevention of Vitamin D Deficiency
In the skin, 7-dehydrocholesterol is converted to previtamin D₃ via UVB light, followed by subsequent conversion to vitamin D₃. Dietary sources are in the form of either vitamin D₂ or D₃, both of which are converted in the liver to 25-hydroxyvitamin D, the major circulating metabolite. In the kidneys, 25-hydroxyvitamin D is then converted to 1,25-dihydroxyvitamin D, the biologically active form. Paradoxically, serum levels of 1,25-dihydroxyvitamin D can be normal or high in the setting of vitamin D deficiency; therefore, serum total 25-hydroxyvitamin D is the best way to assess a patient’s vitamin D status.^5,13

The optimal serum 25-hydroxyvitamin D level is controversial. Recommendations range between 20 to 40 ng/mL¹⁴ and 30 to 50 ng/mL.^13,15,16 Vitamin D levels higher than 50 ng/mL have been correlated with an increased risk of bone fractures and certain cancers.^16-18 Vitamin D toxicity usually is noted in serum levels greater than 88 ng/mL; symptoms of toxicity include hypercalcemia, nausea, vomiting, and muscle weakness. For nondeficient patients, the National Academy of Medicine (formerly the Institute of Medicine) recommended an upper limit of 4000 IU daily.¹⁴ The optimal dose in preventing vitamin D deficiency ranges from 600 to 1000 IU daily.^13-15

Treatment of Vitamin D Deficiency
In the setting of vitamin D deficiency, the amount required for repletion often is dependent on each individual’s ability to absorb and convert to 25-hydroxyvitamin D. Typically every 100 IU of vitamin D correlates with a 0.7 to 1.0 ng/mL increase in serum 25-hydroxyvitamin D levels.¹⁹ There are multiple dosing regimens used to achieve the desired serum 25-hydroxyvitamin D levels in deficient patients. One recommendation from the Endocrine Society is 50,000 IU once weekly for 6 to 8 weeks (single doses >50,000 IU typically are not recommended due to increased risk for toxicity), followed by 600 to 1000 IU once daily in children and 1500 to 2000 IU once daily in adults thereafter.¹³ In patients with vitamin D deficiency, reassessment of serum 25-hydroxyvitamin D levels is recommended after 3 to 4 months of treatment, and adjustments to the repletion regimen should be made as needed.^15,16 Generally, vitamin D₃ is recommended over vitamin D₂ due to enhanced efficacy in raising serum 25-hydroxyvitamin D levels.²⁰

Vitamin D Deficiency in Alopecia
Although most recommendations are given in the interest of optimizing bone health, in the setting of alopecia, we set a similar serum 25-hydroxyvitamin D goal of greater than 30 ng/mL. We recommend treatment with vitamin D₃ and practice the following repletion protocol: 50,000 IU once weekly for 4 weeks, followed by 1000 IU once daily for at least 8 weeks for serum 25-hydroxyvitamin D levels less than 20 ng/mL. For serum hydroxyvitamin D levels between 20 and 29 ng/mL, we recommend 1000 IU once daily for at least 12 weeks. We recheck blood levels again in 3 months. If levels fail to normalize, we will refer the patient to endocrinology. If levels return to normal, we transition to a daily multivitamin with vitamin D (400–800 IU) once daily and refer the patient back to the primary care physician for long-term monitoring.

Social media has become a prominent source of medical information for patients, including those with dermatologic conditions.^1,2 Physicians, patients, and pharmaceutical companies can use social media platforms to communicate with each other and share knowledge and advertisements related to conditions. Social media can influence patients’ perceptions of their disease and serve as a modality to acquire medical treatments.³ Furthermore, social media posts from illicit pharmacies can result in patients buying harmful medications without physician oversight.^4,5 Examination of the content and sources of social media posts related to acne may be useful in determining those who are primarily utilizing social media and for what purpose. The goal of this systematic review was to identify sources of acne-related social media posts to determine communication trends to gain a better understanding of the potential impact social media may have on patient care.

Methods

Social media posts were identified (May 2008 to May 2016) using the search terms acne and treatment across all social media platforms available through a commercial social media data aggregating software (Crimson Hexagon). Information from relevant posts was extracted and compiled into a spreadsheet that included the content, post date, social media platform, and hyperlink. To further analyze the data, the first 100 posts on acne treatment from May 2008 to May 2016 were selected and manually classified by the following types of communication: (1) patient-to-patient (eg, testimonies of patients’ medical experiences); (2) professional-to-patient (eg, clinical knowledge or experience provided by a medical provider and/or cited article in reference to relevant treatments); (3) pharmaceutical company–to-patient (eg, information from reputable drug manufacturers regarding drug activity and adverse effects); (4) illicit pharmacy–to-patient (eg, pharmacies with advertisements calling patients to buy a drug online or offering discrete shipping without a prescription)^4,5; or (5) other-to-patient (eg, posts that did not contain enough detail to be classified).

Results

Hundreds of thousands of social media posts discussing acne treatment were identified over the 8-year study period (Figure 1). The social media data aggregator extracted posts from various blogs, website comment sections, and online forums, as well as major social media platforms (ie, Facebook, Twitter, Google+, Tumblr). The first 100 posts selected for further analysis included 0 from 2008, 6 from 2009, 36 from 2010, 15 from 2011, 7 from 2012, 8 from 2013, 12 from 2014, 11 from 2015, and 5 from 2016. From this sample, 65 posts were considered to have an illicit source; conversely, 18 posts were from patients and 7 posts were from pharmaceutical companies (Figure 2).

Comment

This study demonstrated that discussion of acne treatment is prevalent in social media. Although our research underrepresents the social media interest in specific acne treatments, as only posts mentioning the terms acne and treatment were evaluated to gain insights into how social media platforms are being used by individuals with cutaneous disease. As such, even with this potential underrepresentation, our study demonstrated a high incidence of illicit marketing of prescription acne medications across multiple social media platforms (Figure 2). The sale of dermatologic pharmaceuticals (eg, isotretinoin) without a prescription is recognized by the US Government as a problem that is rapidly growing.^4,5 Illicit pharmacies pose as legitimate pharmacies that can provide prescription medications to consumers without a prescription.^5,6 The fact that these illicit pharmacy–to-patient posts were the most abundant in our study may speak to their relative success on social media platforms in encouraging patients to purchase prescription medications without physician oversight. These findings should concern health care providers, as the procurement of prescription medications without a prescription may put patients at risk.

Social media has become a prominent source of medical information for patients, including those with dermatologic conditions.^1,2 Physicians, patients, and pharmaceutical companies can use social media platforms to communicate with each other and share knowledge and advertisements related to conditions. Social media can influence patients’ perceptions of their disease and serve as a modality to acquire medical treatments.³ Furthermore, social media posts from illicit pharmacies can result in patients buying harmful medications without physician oversight.^4,5 Examination of the content and sources of social media posts related to acne may be useful in determining those who are primarily utilizing social media and for what purpose. The goal of this systematic review was to identify sources of acne-related social media posts to determine communication trends to gain a better understanding of the potential impact social media may have on patient care.

Methods

Social media posts were identified (May 2008 to May 2016) using the search terms acne and treatment across all social media platforms available through a commercial social media data aggregating software (Crimson Hexagon). Information from relevant posts was extracted and compiled into a spreadsheet that included the content, post date, social media platform, and hyperlink. To further analyze the data, the first 100 posts on acne treatment from May 2008 to May 2016 were selected and manually classified by the following types of communication: (1) patient-to-patient (eg, testimonies of patients’ medical experiences); (2) professional-to-patient (eg, clinical knowledge or experience provided by a medical provider and/or cited article in reference to relevant treatments); (3) pharmaceutical company–to-patient (eg, information from reputable drug manufacturers regarding drug activity and adverse effects); (4) illicit pharmacy–to-patient (eg, pharmacies with advertisements calling patients to buy a drug online or offering discrete shipping without a prescription)^4,5; or (5) other-to-patient (eg, posts that did not contain enough detail to be classified).

Results

Hundreds of thousands of social media posts discussing acne treatment were identified over the 8-year study period (Figure 1). The social media data aggregator extracted posts from various blogs, website comment sections, and online forums, as well as major social media platforms (ie, Facebook, Twitter, Google+, Tumblr). The first 100 posts selected for further analysis included 0 from 2008, 6 from 2009, 36 from 2010, 15 from 2011, 7 from 2012, 8 from 2013, 12 from 2014, 11 from 2015, and 5 from 2016. From this sample, 65 posts were considered to have an illicit source; conversely, 18 posts were from patients and 7 posts were from pharmaceutical companies (Figure 2).

Comment

This study demonstrated that discussion of acne treatment is prevalent in social media. Although our research underrepresents the social media interest in specific acne treatments, as only posts mentioning the terms acne and treatment were evaluated to gain insights into how social media platforms are being used by individuals with cutaneous disease. As such, even with this potential underrepresentation, our study demonstrated a high incidence of illicit marketing of prescription acne medications across multiple social media platforms (Figure 2). The sale of dermatologic pharmaceuticals (eg, isotretinoin) without a prescription is recognized by the US Government as a problem that is rapidly growing.^4,5 Illicit pharmacies pose as legitimate pharmacies that can provide prescription medications to consumers without a prescription.^5,6 The fact that these illicit pharmacy–to-patient posts were the most abundant in our study may speak to their relative success on social media platforms in encouraging patients to purchase prescription medications without physician oversight. These findings should concern health care providers, as the procurement of prescription medications without a prescription may put patients at risk.

Social media has become a prominent source of medical information for patients, including those with dermatologic conditions.^1,2 Physicians, patients, and pharmaceutical companies can use social media platforms to communicate with each other and share knowledge and advertisements related to conditions. Social media can influence patients’ perceptions of their disease and serve as a modality to acquire medical treatments.³ Furthermore, social media posts from illicit pharmacies can result in patients buying harmful medications without physician oversight.^4,5 Examination of the content and sources of social media posts related to acne may be useful in determining those who are primarily utilizing social media and for what purpose. The goal of this systematic review was to identify sources of acne-related social media posts to determine communication trends to gain a better understanding of the potential impact social media may have on patient care.

Methods

Social media posts were identified (May 2008 to May 2016) using the search terms acne and treatment across all social media platforms available through a commercial social media data aggregating software (Crimson Hexagon). Information from relevant posts was extracted and compiled into a spreadsheet that included the content, post date, social media platform, and hyperlink. To further analyze the data, the first 100 posts on acne treatment from May 2008 to May 2016 were selected and manually classified by the following types of communication: (1) patient-to-patient (eg, testimonies of patients’ medical experiences); (2) professional-to-patient (eg, clinical knowledge or experience provided by a medical provider and/or cited article in reference to relevant treatments); (3) pharmaceutical company–to-patient (eg, information from reputable drug manufacturers regarding drug activity and adverse effects); (4) illicit pharmacy–to-patient (eg, pharmacies with advertisements calling patients to buy a drug online or offering discrete shipping without a prescription)^4,5; or (5) other-to-patient (eg, posts that did not contain enough detail to be classified).

Results

Hundreds of thousands of social media posts discussing acne treatment were identified over the 8-year study period (Figure 1). The social media data aggregator extracted posts from various blogs, website comment sections, and online forums, as well as major social media platforms (ie, Facebook, Twitter, Google+, Tumblr). The first 100 posts selected for further analysis included 0 from 2008, 6 from 2009, 36 from 2010, 15 from 2011, 7 from 2012, 8 from 2013, 12 from 2014, 11 from 2015, and 5 from 2016. From this sample, 65 posts were considered to have an illicit source; conversely, 18 posts were from patients and 7 posts were from pharmaceutical companies (Figure 2).

Comment

This study demonstrated that discussion of acne treatment is prevalent in social media. Although our research underrepresents the social media interest in specific acne treatments, as only posts mentioning the terms acne and treatment were evaluated to gain insights into how social media platforms are being used by individuals with cutaneous disease. As such, even with this potential underrepresentation, our study demonstrated a high incidence of illicit marketing of prescription acne medications across multiple social media platforms (Figure 2). The sale of dermatologic pharmaceuticals (eg, isotretinoin) without a prescription is recognized by the US Government as a problem that is rapidly growing.^4,5 Illicit pharmacies pose as legitimate pharmacies that can provide prescription medications to consumers without a prescription.^5,6 The fact that these illicit pharmacy–to-patient posts were the most abundant in our study may speak to their relative success on social media platforms in encouraging patients to purchase prescription medications without physician oversight. These findings should concern health care providers, as the procurement of prescription medications without a prescription may put patients at risk.

The Centers for Medicare & Medicaid Services announced July 7 that it will no longer make adjustment payments to insurers until litigation regarding them is resolved, further destabilizing the individual and small group markets created by the Affordable Care Act.

The risk adjustment payment uses statewide average premiums to draw money from health insurance plans within a state that have low levels of high-need patients and funnels that money to plans in that state with high amounts of high-need patients, as a way to minimize adverse selection and to spread risk.

The government was set to make a budget neutral payment of $10.4 billion for the 2017 plan year. But in a rare Saturday announcement, the agency said July 7 that the reason for putting the risk adjustment payments on hold was differing legal opinions on the validity of the payments.

designer491/Thinkstock

[email protected]

The Centers for Medicare & Medicaid Services announced July 7 that it will no longer make adjustment payments to insurers until litigation regarding them is resolved, further destabilizing the individual and small group markets created by the Affordable Care Act.

The risk adjustment payment uses statewide average premiums to draw money from health insurance plans within a state that have low levels of high-need patients and funnels that money to plans in that state with high amounts of high-need patients, as a way to minimize adverse selection and to spread risk.

The government was set to make a budget neutral payment of $10.4 billion for the 2017 plan year. But in a rare Saturday announcement, the agency said July 7 that the reason for putting the risk adjustment payments on hold was differing legal opinions on the validity of the payments.

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[email protected]

The Centers for Medicare & Medicaid Services announced July 7 that it will no longer make adjustment payments to insurers until litigation regarding them is resolved, further destabilizing the individual and small group markets created by the Affordable Care Act.

The risk adjustment payment uses statewide average premiums to draw money from health insurance plans within a state that have low levels of high-need patients and funnels that money to plans in that state with high amounts of high-need patients, as a way to minimize adverse selection and to spread risk.

The government was set to make a budget neutral payment of $10.4 billion for the 2017 plan year. But in a rare Saturday announcement, the agency said July 7 that the reason for putting the risk adjustment payments on hold was differing legal opinions on the validity of the payments.

designer491/Thinkstock

[email protected]

For patients with non–high-risk acute promyelocytic leukemia (APML), the combination of an oral arsenic formulation and all-trans retinoic acid (ATRA) was noninferior to standard therapy with intravenous arsenic trioxide and ATRA, results of a randomized phase 3 trial show.

Among 109 patients with APML from one of 14 centers in China, the 2-year event-free survival rate after a median follow-up of 32 months was 97% for patients randomized to receive oral arsenic realgar-Indigo naturalis formula (RIF) plus ATRA, and 94% for patients randomized to IV arsenic trioxide plus ATRA, reported Hong-Hu Zhu, MD, of Peking University People’s Hospital in Beijing, China, and his colleagues.

“Our results suggest that non–high-risk acute promyelocytic leukemia can be cured using complete oral arsenic plus ATRA without conventional chemotherapy,” the investigators wrote. The report was published in The Lancet Oncology. “Although longer-term follow-up is needed to draw firm conclusions, our results support previously reported clinical and experimental evidence indicating that ATRA and arsenic act synergistically to eradicate acute promyelocytic leukemia.”

The combination of IV arsenic trioxide and ATRA has revolutionized the care of patients with APML, producing complete and durable remissions in more than 95% of patients with non–high-risk disease, defined as white blood cell counts of 10 x 10⁹/L or less. The trial was designed to see whether an easier-to-administer all-oral regimen could be similarly efficacious and safe, the investigators said.

A total of 109 patients with newly diagnosed APML were randomly assigned on 2:1 basis to receive either RIF-ATRA (72 patients) or arsenic trioxide ATRA (37). Three patients in the oral arm and one in the arsenic trioxide arm did not receive the assigned therapy, but instead received ATRA and chemotherapy.

For induction, RIF was delivered 60 mg/kg daily in an oral divided dose; arsenic trioxide was delivered 0.15 mg/kg daily in an IV. ATRA was delivered 25 mg/m² daily in an oral divided dose. Treatments were used until complete remissions were achieved.

Consolidation was home based and consisted of the same daily doses of RIF or arsenic trioxide in a 4-week-on/4-week-off regimen for four cycles, plus ATRA in the same daily dose in a 2-week-on/2-week-off regimen for seven cycles.

In a modified intention-to-treat analysis with 105 patients, 2-year EFS rates (the primary endpoint) were 97% with oral arsenic and 94% with arsenic trioxide. The percentage difference in EFS was 2.7% and RIF met the prespecified requirement for noninferiority because the lower limit of the 95% confidence interval (-5.8%) was greater than the noninferiority margin of –10%. The noninferiority of the oral formulation was confirmed in a per-protocol analysis, the investigators noted.

Grade 3 or 4 hepatotoxicities during induction were seen in 9% of patients treated with RIF-ATRA versus 14% of patients in the arsenic trioxide–ATRA group. Grade 3 or 4 infections occurred in 23% and 42% of patients, respectively.

Two patients in the arsenic trioxide–ATRA group died during induction therapy, one from hemorrhage and one from thrombocytopenia. There were no deaths during induction in the RIF-ATRA arm and no additional deaths in either arm during the consolidation phase.

All of the 103 surviving patients achieved complete remissions after consolidation.

The investigators acknowledged that the study was limited by a median follow-up time that was too short to allow definitive conclusions about overall survival. They plan to compare the costs of the two regimens in a future study.

SOURCE: Zhu HH et al. Lancet Oncol 2018;19:871-9.

For patients with non–high-risk acute promyelocytic leukemia (APML), the combination of an oral arsenic formulation and all-trans retinoic acid (ATRA) was noninferior to standard therapy with intravenous arsenic trioxide and ATRA, results of a randomized phase 3 trial show.

Among 109 patients with APML from one of 14 centers in China, the 2-year event-free survival rate after a median follow-up of 32 months was 97% for patients randomized to receive oral arsenic realgar-Indigo naturalis formula (RIF) plus ATRA, and 94% for patients randomized to IV arsenic trioxide plus ATRA, reported Hong-Hu Zhu, MD, of Peking University People’s Hospital in Beijing, China, and his colleagues.

“Our results suggest that non–high-risk acute promyelocytic leukemia can be cured using complete oral arsenic plus ATRA without conventional chemotherapy,” the investigators wrote. The report was published in The Lancet Oncology. “Although longer-term follow-up is needed to draw firm conclusions, our results support previously reported clinical and experimental evidence indicating that ATRA and arsenic act synergistically to eradicate acute promyelocytic leukemia.”

The combination of IV arsenic trioxide and ATRA has revolutionized the care of patients with APML, producing complete and durable remissions in more than 95% of patients with non–high-risk disease, defined as white blood cell counts of 10 x 10⁹/L or less. The trial was designed to see whether an easier-to-administer all-oral regimen could be similarly efficacious and safe, the investigators said.

A total of 109 patients with newly diagnosed APML were randomly assigned on 2:1 basis to receive either RIF-ATRA (72 patients) or arsenic trioxide ATRA (37). Three patients in the oral arm and one in the arsenic trioxide arm did not receive the assigned therapy, but instead received ATRA and chemotherapy.

For induction, RIF was delivered 60 mg/kg daily in an oral divided dose; arsenic trioxide was delivered 0.15 mg/kg daily in an IV. ATRA was delivered 25 mg/m² daily in an oral divided dose. Treatments were used until complete remissions were achieved.

Consolidation was home based and consisted of the same daily doses of RIF or arsenic trioxide in a 4-week-on/4-week-off regimen for four cycles, plus ATRA in the same daily dose in a 2-week-on/2-week-off regimen for seven cycles.

In a modified intention-to-treat analysis with 105 patients, 2-year EFS rates (the primary endpoint) were 97% with oral arsenic and 94% with arsenic trioxide. The percentage difference in EFS was 2.7% and RIF met the prespecified requirement for noninferiority because the lower limit of the 95% confidence interval (-5.8%) was greater than the noninferiority margin of –10%. The noninferiority of the oral formulation was confirmed in a per-protocol analysis, the investigators noted.

Grade 3 or 4 hepatotoxicities during induction were seen in 9% of patients treated with RIF-ATRA versus 14% of patients in the arsenic trioxide–ATRA group. Grade 3 or 4 infections occurred in 23% and 42% of patients, respectively.

Two patients in the arsenic trioxide–ATRA group died during induction therapy, one from hemorrhage and one from thrombocytopenia. There were no deaths during induction in the RIF-ATRA arm and no additional deaths in either arm during the consolidation phase.

All of the 103 surviving patients achieved complete remissions after consolidation.

The investigators acknowledged that the study was limited by a median follow-up time that was too short to allow definitive conclusions about overall survival. They plan to compare the costs of the two regimens in a future study.

SOURCE: Zhu HH et al. Lancet Oncol 2018;19:871-9.

For patients with non–high-risk acute promyelocytic leukemia (APML), the combination of an oral arsenic formulation and all-trans retinoic acid (ATRA) was noninferior to standard therapy with intravenous arsenic trioxide and ATRA, results of a randomized phase 3 trial show.

Among 109 patients with APML from one of 14 centers in China, the 2-year event-free survival rate after a median follow-up of 32 months was 97% for patients randomized to receive oral arsenic realgar-Indigo naturalis formula (RIF) plus ATRA, and 94% for patients randomized to IV arsenic trioxide plus ATRA, reported Hong-Hu Zhu, MD, of Peking University People’s Hospital in Beijing, China, and his colleagues.

“Our results suggest that non–high-risk acute promyelocytic leukemia can be cured using complete oral arsenic plus ATRA without conventional chemotherapy,” the investigators wrote. The report was published in The Lancet Oncology. “Although longer-term follow-up is needed to draw firm conclusions, our results support previously reported clinical and experimental evidence indicating that ATRA and arsenic act synergistically to eradicate acute promyelocytic leukemia.”

The combination of IV arsenic trioxide and ATRA has revolutionized the care of patients with APML, producing complete and durable remissions in more than 95% of patients with non–high-risk disease, defined as white blood cell counts of 10 x 10⁹/L or less. The trial was designed to see whether an easier-to-administer all-oral regimen could be similarly efficacious and safe, the investigators said.

A total of 109 patients with newly diagnosed APML were randomly assigned on 2:1 basis to receive either RIF-ATRA (72 patients) or arsenic trioxide ATRA (37). Three patients in the oral arm and one in the arsenic trioxide arm did not receive the assigned therapy, but instead received ATRA and chemotherapy.

For induction, RIF was delivered 60 mg/kg daily in an oral divided dose; arsenic trioxide was delivered 0.15 mg/kg daily in an IV. ATRA was delivered 25 mg/m² daily in an oral divided dose. Treatments were used until complete remissions were achieved.

Consolidation was home based and consisted of the same daily doses of RIF or arsenic trioxide in a 4-week-on/4-week-off regimen for four cycles, plus ATRA in the same daily dose in a 2-week-on/2-week-off regimen for seven cycles.

In a modified intention-to-treat analysis with 105 patients, 2-year EFS rates (the primary endpoint) were 97% with oral arsenic and 94% with arsenic trioxide. The percentage difference in EFS was 2.7% and RIF met the prespecified requirement for noninferiority because the lower limit of the 95% confidence interval (-5.8%) was greater than the noninferiority margin of –10%. The noninferiority of the oral formulation was confirmed in a per-protocol analysis, the investigators noted.

Grade 3 or 4 hepatotoxicities during induction were seen in 9% of patients treated with RIF-ATRA versus 14% of patients in the arsenic trioxide–ATRA group. Grade 3 or 4 infections occurred in 23% and 42% of patients, respectively.

Two patients in the arsenic trioxide–ATRA group died during induction therapy, one from hemorrhage and one from thrombocytopenia. There were no deaths during induction in the RIF-ATRA arm and no additional deaths in either arm during the consolidation phase.

All of the 103 surviving patients achieved complete remissions after consolidation.

The investigators acknowledged that the study was limited by a median follow-up time that was too short to allow definitive conclusions about overall survival. They plan to compare the costs of the two regimens in a future study.

SOURCE: Zhu HH et al. Lancet Oncol 2018;19:871-9.

Intensive use of nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with improved survival of patients with serous ovarian cancer in a recent population-based study.

By contrast, any use of nonaspirin NSAIDs was not associated with survival benefit, according to the authors of the study, which was based on records for more than 4,000 patients in the Danish Cancer Registry.

“More intensive use of nonaspirin NSAIDs appears necessary to obtain a prognostic benefit,” wrote Freija Verdoodt, PhD, postdoctoral researcher with the Danish Cancer Society Research Center, Copenhagen and her coauthors. The report was published in Gynecologic Oncology.

In addition, there was a suggestion that use of these drugs was associated with increased mortality in patients that with nonserous ovarian cancer, Dr. Verdoodt and her colleagues noted.

The study population comprised 4,117 women who were alive 1 year after a diagnosis of epithelial ovarian cancer. Ovarian cancer–specific mortality, the primary outcome of the analysis, was evaluated in relation to postdiagnosis use of nonaspirin NSAIDs.

The investigators found that any postdiagnosis use of nonaspirin NSAIDs was not associated with a difference in mortality, with a hazard ratio of 0.97 (95% confidence interval, 0.87-1.08) after adjusting for factors such as age, clinical stage, and year of diagnosis.

“Nonaspirin NSAIDs are typically used sporadically, and thus limited use among a substantial proportion of the postdiagnosis users may have attenuated the mortality risk estimates of our main analysis,” Dr. Verdoodt and her coauthors wrote.

However, increasing cumulative dose was associated with decreases in mortality, with hazard ratios of 1.03, 0.96, and 0.75 for low, medium, and high cumulative doses, respectively.

Likewise, the intensity of use, defined as cumulative dose divided by the number of days between the first and most recent postdiagnosis NSAID prescription, was associated with decreased mortality, with hazard ratios of 1.04, 0.98, and 0.86 for low, medium, and high use intensity, the reported data show.

When stratified by tumor histology, the data showed an association between reduced ovarian cancer–specific mortality and serous ovarian tumors (hazard ratio, 0.87; 95% CI, 0.77-0.99), and post hoc analyses confirmed further reductions in mortality based on high cumulative doses, with a hazard ratio of 0.62, and high intensity of use, with a hazard ratio of 0.79.

Conversely, other histologies were associated with increases in ovarian cancer mortality, though the numbers of patients in these subgroups were small, limiting interpretation of the results, investigators said.

Prior to this study, there were few epidemiologic investigations of the impact of nonaspirin NSAIDs on ovarian cancer prognosis, and of those, most did not include separate estimates based on histological subtypes, according to the investigators.

Although this study suggests intensive nonaspirin NSAID use comes with a potential prognostic benefit, these drugs also have potential adverse effects, including serious cardiovascular adverse events, the investigators said.

“A consideration of such risks in the light of a survival benefit among poor-prognosis serous ovarian cancer patients should guide further research,” they wrote.

The study was supported by the Sapere Aude program of the Independent Research Fund Denmark and the Mermaid project. The authors declared no conflicts of interest.

SOURCE: Verdoodt F et al. Gynecol Oncol. 2018 Jun 27. doi: 10.1016/j.ygyno.2018.06.018.

Intensive use of nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with improved survival of patients with serous ovarian cancer in a recent population-based study.

By contrast, any use of nonaspirin NSAIDs was not associated with survival benefit, according to the authors of the study, which was based on records for more than 4,000 patients in the Danish Cancer Registry.

“More intensive use of nonaspirin NSAIDs appears necessary to obtain a prognostic benefit,” wrote Freija Verdoodt, PhD, postdoctoral researcher with the Danish Cancer Society Research Center, Copenhagen and her coauthors. The report was published in Gynecologic Oncology.

In addition, there was a suggestion that use of these drugs was associated with increased mortality in patients that with nonserous ovarian cancer, Dr. Verdoodt and her colleagues noted.

The study population comprised 4,117 women who were alive 1 year after a diagnosis of epithelial ovarian cancer. Ovarian cancer–specific mortality, the primary outcome of the analysis, was evaluated in relation to postdiagnosis use of nonaspirin NSAIDs.

The investigators found that any postdiagnosis use of nonaspirin NSAIDs was not associated with a difference in mortality, with a hazard ratio of 0.97 (95% confidence interval, 0.87-1.08) after adjusting for factors such as age, clinical stage, and year of diagnosis.

“Nonaspirin NSAIDs are typically used sporadically, and thus limited use among a substantial proportion of the postdiagnosis users may have attenuated the mortality risk estimates of our main analysis,” Dr. Verdoodt and her coauthors wrote.

However, increasing cumulative dose was associated with decreases in mortality, with hazard ratios of 1.03, 0.96, and 0.75 for low, medium, and high cumulative doses, respectively.

Likewise, the intensity of use, defined as cumulative dose divided by the number of days between the first and most recent postdiagnosis NSAID prescription, was associated with decreased mortality, with hazard ratios of 1.04, 0.98, and 0.86 for low, medium, and high use intensity, the reported data show.

When stratified by tumor histology, the data showed an association between reduced ovarian cancer–specific mortality and serous ovarian tumors (hazard ratio, 0.87; 95% CI, 0.77-0.99), and post hoc analyses confirmed further reductions in mortality based on high cumulative doses, with a hazard ratio of 0.62, and high intensity of use, with a hazard ratio of 0.79.

Conversely, other histologies were associated with increases in ovarian cancer mortality, though the numbers of patients in these subgroups were small, limiting interpretation of the results, investigators said.

Prior to this study, there were few epidemiologic investigations of the impact of nonaspirin NSAIDs on ovarian cancer prognosis, and of those, most did not include separate estimates based on histological subtypes, according to the investigators.

Although this study suggests intensive nonaspirin NSAID use comes with a potential prognostic benefit, these drugs also have potential adverse effects, including serious cardiovascular adverse events, the investigators said.

“A consideration of such risks in the light of a survival benefit among poor-prognosis serous ovarian cancer patients should guide further research,” they wrote.

The study was supported by the Sapere Aude program of the Independent Research Fund Denmark and the Mermaid project. The authors declared no conflicts of interest.

SOURCE: Verdoodt F et al. Gynecol Oncol. 2018 Jun 27. doi: 10.1016/j.ygyno.2018.06.018.

Intensive use of nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) was associated with improved survival of patients with serous ovarian cancer in a recent population-based study.

By contrast, any use of nonaspirin NSAIDs was not associated with survival benefit, according to the authors of the study, which was based on records for more than 4,000 patients in the Danish Cancer Registry.

“More intensive use of nonaspirin NSAIDs appears necessary to obtain a prognostic benefit,” wrote Freija Verdoodt, PhD, postdoctoral researcher with the Danish Cancer Society Research Center, Copenhagen and her coauthors. The report was published in Gynecologic Oncology.

In addition, there was a suggestion that use of these drugs was associated with increased mortality in patients that with nonserous ovarian cancer, Dr. Verdoodt and her colleagues noted.

The study population comprised 4,117 women who were alive 1 year after a diagnosis of epithelial ovarian cancer. Ovarian cancer–specific mortality, the primary outcome of the analysis, was evaluated in relation to postdiagnosis use of nonaspirin NSAIDs.

The investigators found that any postdiagnosis use of nonaspirin NSAIDs was not associated with a difference in mortality, with a hazard ratio of 0.97 (95% confidence interval, 0.87-1.08) after adjusting for factors such as age, clinical stage, and year of diagnosis.

“Nonaspirin NSAIDs are typically used sporadically, and thus limited use among a substantial proportion of the postdiagnosis users may have attenuated the mortality risk estimates of our main analysis,” Dr. Verdoodt and her coauthors wrote.

However, increasing cumulative dose was associated with decreases in mortality, with hazard ratios of 1.03, 0.96, and 0.75 for low, medium, and high cumulative doses, respectively.

Likewise, the intensity of use, defined as cumulative dose divided by the number of days between the first and most recent postdiagnosis NSAID prescription, was associated with decreased mortality, with hazard ratios of 1.04, 0.98, and 0.86 for low, medium, and high use intensity, the reported data show.

When stratified by tumor histology, the data showed an association between reduced ovarian cancer–specific mortality and serous ovarian tumors (hazard ratio, 0.87; 95% CI, 0.77-0.99), and post hoc analyses confirmed further reductions in mortality based on high cumulative doses, with a hazard ratio of 0.62, and high intensity of use, with a hazard ratio of 0.79.

Conversely, other histologies were associated with increases in ovarian cancer mortality, though the numbers of patients in these subgroups were small, limiting interpretation of the results, investigators said.

Prior to this study, there were few epidemiologic investigations of the impact of nonaspirin NSAIDs on ovarian cancer prognosis, and of those, most did not include separate estimates based on histological subtypes, according to the investigators.

Although this study suggests intensive nonaspirin NSAID use comes with a potential prognostic benefit, these drugs also have potential adverse effects, including serious cardiovascular adverse events, the investigators said.

“A consideration of such risks in the light of a survival benefit among poor-prognosis serous ovarian cancer patients should guide further research,” they wrote.

The study was supported by the Sapere Aude program of the Independent Research Fund Denmark and the Mermaid project. The authors declared no conflicts of interest.

SOURCE: Verdoodt F et al. Gynecol Oncol. 2018 Jun 27. doi: 10.1016/j.ygyno.2018.06.018.

Individuals who develop acute myeloid leukemia (AML) may have somatic mutations detectable years before diagnosis, a newly published analysis shows.

Mutations in IDH1, IDH2, TP53, DNMT3A, TET2, and spliceosome genes at baseline assessment increased the odds of developing AML with a median follow-up of 9.6 years in the study, which was based on blood samples from participants in the Women’s Health Initiative (WHI).

The findings suggest a “premalignant landscape of mutations” that may precede overt AML by many years, according to Pinkal Desai, MD, assistant professor of medicine at Cornell University and oncologist at New York–Presbyterian/Weill Cornell Medical Center, New York, and her coauthors.

“The ability to detect and identify high-risk mutations suggests that monitoring strategies for patients, as well as clinical trials of potentially preventative or disease-intercepting interventions should be considered,” wrote Dr. Desai and her colleagues. The report was published in Nature Medicine.

Their analysis comprised 212 women who participated in the WHI who were healthy at the baseline evaluation but went on to develop AML during follow-up. They performed deep sequencing on peripheral blood DNA for these cases and for 212 age-matched controls.

Women who developed AML were more likely than were controls to have mutations in baseline assessment (odds ratio, 4.86; 95% confidence interval, 3.07-7.77), and had demonstrated greater clonal complexity versus controls (comutations in 46.8% and 5.5%, respectively; odds ratio, 9.01; 95% CI, 4.1-21.4), investigators found.

©GunarsB/Thinkstock

All 21 patients with TP53 mutations went on to develop AML, as did all 15 with IDH1 or IDH2 mutations and all 3 with RUNX1 mutations. Multivariate analysis showed that TP53, IDH1 and IDH2, TET2, DNMT3A and several spliceosome genes were associated with significantly increased odds of AML versus controls.

Based on these results, Dr. Desai and colleagues proposed that patients at increased AML risk should be followed in long-term monitoring studies that incorporate next-generation sequencing.

“Data from these studies will provide a robust rationale for clinical trials of preventative intervention strategies in populations at high risk of developing AML,” they wrote.

In clinical practice, monitoring individuals for AML-associated mutations will become more feasible as costs decrease and new therapies with favorable toxicity profiles are introduced, they added.

“Molecularly targeted therapy is already available for IDH2 mutations and is under development for mutations in other candidate genes found in this study including IDH1, TP53 and spliceosome genes,” they wrote.

The authors reported having no relevant financial disclosures. The WHI program is funded by the National Institutes of Health.

SOURCE: Desai P et al. Nat Med. 2018;24:1015-23.

Individuals who develop acute myeloid leukemia (AML) may have somatic mutations detectable years before diagnosis, a newly published analysis shows.

Mutations in IDH1, IDH2, TP53, DNMT3A, TET2, and spliceosome genes at baseline assessment increased the odds of developing AML with a median follow-up of 9.6 years in the study, which was based on blood samples from participants in the Women’s Health Initiative (WHI).

The findings suggest a “premalignant landscape of mutations” that may precede overt AML by many years, according to Pinkal Desai, MD, assistant professor of medicine at Cornell University and oncologist at New York–Presbyterian/Weill Cornell Medical Center, New York, and her coauthors.

“The ability to detect and identify high-risk mutations suggests that monitoring strategies for patients, as well as clinical trials of potentially preventative or disease-intercepting interventions should be considered,” wrote Dr. Desai and her colleagues. The report was published in Nature Medicine.

Their analysis comprised 212 women who participated in the WHI who were healthy at the baseline evaluation but went on to develop AML during follow-up. They performed deep sequencing on peripheral blood DNA for these cases and for 212 age-matched controls.

Women who developed AML were more likely than were controls to have mutations in baseline assessment (odds ratio, 4.86; 95% confidence interval, 3.07-7.77), and had demonstrated greater clonal complexity versus controls (comutations in 46.8% and 5.5%, respectively; odds ratio, 9.01; 95% CI, 4.1-21.4), investigators found.

©GunarsB/Thinkstock

All 21 patients with TP53 mutations went on to develop AML, as did all 15 with IDH1 or IDH2 mutations and all 3 with RUNX1 mutations. Multivariate analysis showed that TP53, IDH1 and IDH2, TET2, DNMT3A and several spliceosome genes were associated with significantly increased odds of AML versus controls.

Based on these results, Dr. Desai and colleagues proposed that patients at increased AML risk should be followed in long-term monitoring studies that incorporate next-generation sequencing.

“Data from these studies will provide a robust rationale for clinical trials of preventative intervention strategies in populations at high risk of developing AML,” they wrote.

In clinical practice, monitoring individuals for AML-associated mutations will become more feasible as costs decrease and new therapies with favorable toxicity profiles are introduced, they added.

“Molecularly targeted therapy is already available for IDH2 mutations and is under development for mutations in other candidate genes found in this study including IDH1, TP53 and spliceosome genes,” they wrote.

The authors reported having no relevant financial disclosures. The WHI program is funded by the National Institutes of Health.

SOURCE: Desai P et al. Nat Med. 2018;24:1015-23.

Individuals who develop acute myeloid leukemia (AML) may have somatic mutations detectable years before diagnosis, a newly published analysis shows.

Mutations in IDH1, IDH2, TP53, DNMT3A, TET2, and spliceosome genes at baseline assessment increased the odds of developing AML with a median follow-up of 9.6 years in the study, which was based on blood samples from participants in the Women’s Health Initiative (WHI).

The findings suggest a “premalignant landscape of mutations” that may precede overt AML by many years, according to Pinkal Desai, MD, assistant professor of medicine at Cornell University and oncologist at New York–Presbyterian/Weill Cornell Medical Center, New York, and her coauthors.

“The ability to detect and identify high-risk mutations suggests that monitoring strategies for patients, as well as clinical trials of potentially preventative or disease-intercepting interventions should be considered,” wrote Dr. Desai and her colleagues. The report was published in Nature Medicine.

Their analysis comprised 212 women who participated in the WHI who were healthy at the baseline evaluation but went on to develop AML during follow-up. They performed deep sequencing on peripheral blood DNA for these cases and for 212 age-matched controls.

Women who developed AML were more likely than were controls to have mutations in baseline assessment (odds ratio, 4.86; 95% confidence interval, 3.07-7.77), and had demonstrated greater clonal complexity versus controls (comutations in 46.8% and 5.5%, respectively; odds ratio, 9.01; 95% CI, 4.1-21.4), investigators found.

©GunarsB/Thinkstock

All 21 patients with TP53 mutations went on to develop AML, as did all 15 with IDH1 or IDH2 mutations and all 3 with RUNX1 mutations. Multivariate analysis showed that TP53, IDH1 and IDH2, TET2, DNMT3A and several spliceosome genes were associated with significantly increased odds of AML versus controls.

Based on these results, Dr. Desai and colleagues proposed that patients at increased AML risk should be followed in long-term monitoring studies that incorporate next-generation sequencing.

“Data from these studies will provide a robust rationale for clinical trials of preventative intervention strategies in populations at high risk of developing AML,” they wrote.

In clinical practice, monitoring individuals for AML-associated mutations will become more feasible as costs decrease and new therapies with favorable toxicity profiles are introduced, they added.

“Molecularly targeted therapy is already available for IDH2 mutations and is under development for mutations in other candidate genes found in this study including IDH1, TP53 and spliceosome genes,” they wrote.

The authors reported having no relevant financial disclosures. The WHI program is funded by the National Institutes of Health.

SOURCE: Desai P et al. Nat Med. 2018;24:1015-23.

Abstract

• Objective: To review the diagnosis and management of aggressive B-cell non-Hodgkin lymphoma (NHL).
• Methods: Review of the literature.
• Results: NHL comprises a wide variety of malignant hematologic disorders with varying clinical and biological features. Aggressive NHLs are characterized by rapid clinical progression without therapy. However, a significant proportion of patients are cured with appropriate combination chemotherapy or combined modality regimens. In contrast, the indolent lymphomas have a relatively good prognosis (median survival of 10 years or longer) but usually are not curable in advanced clinical stages. Overall 5-year survival for aggressive NHLs with current treatment is approximately 50% to 60%, with relapses typically occurring within the first 5 years.
• Conclusion: Treatment strategies for relapsed patients offer some potential for cure; however, clinical trial participation should be encouraged whenever possible to investigate new approaches for improving outcomes in this patient population.

Non-Hodgkin lymphoma (NHL) comprises a wide variety of malignant hematologic disorders with varying clinical and biological features. The more than 60 separate NHL subtypes can be classified according to cell of origin (B cell versus T cell), anatomical location (eg, orbital, testicular, bone, central nervous system), clinical behavior (indolent versus aggressive), histological features, or cytogenetic abnormalities. Although various NHL classification schemes have been used over the years, the World Health Organization (WHO) classification is now widely accepted as the definitive pathologic classification system for lymphoproliferative disorders, incorporating morphologic, immunohistochemical, flow cytometric, cytogenetic, and molecular features [1]. While the pathologic and molecular subclassification of NHL has become increasingly refined in recent years, from a management standpoint, classification based on clinical behavior remains very useful. This approach separates NHL subtypes into indolent versus aggressive categories. Whereas indolent NHLs may remain clinically insignificant for months to years, aggressive B-cell NHLs generally become life-threatening within weeks to months without treatment.

Epidemiology

Data from cancer registries show a steady, unexplainable increase in the incidence of NHL during the second half of the 20th century; the incidence has subsequently plateaued. There was a significant increase in NHL incidence between 1970 and 1995, which has been attributed in part to the HIV epidemic. More than 72,000 new cases of NHL were diagnosed in the United States in 2017, compared to just over 8000 cases of Hodgkin lymphoma, making NHL the sixth most common cancer in adult men and the fifth most common in adult women [2]. NHL appears to occur more frequently in Western countries than in Asian populations.

Various factors associated with increased risk for B-cell NHL have been identified over the years, including occupational and environmental exposure to certain pesticides and herbicides [3], immunosuppression associated with HIV infection [4], autoimmune disorders [5], iatrogenically induced immune suppression in the post-transplant and other settings [6], family history of NHL [7], and a personal history of a prior cancer, including Hodgkin lymphoma and prior NHL [8]. In terms of infectious agents associated with aggressive B-cell NHLs, Epstein-Barr virus (EBV) has a clear pathogenic role in Burkitt lymphoma, in many cases of post-transplant lymphoproliferative disorders, and in some cases of HIV-related aggressive B-cell lymphoma [9]. Human herpesvirus-8 viral genomes have been found in virtually all cases of primary effusion lymphomas [10]. Epidemiological studies also have linked hepatitis B and C to increased incidences of certain NHL subtypes [11–13], including primary hepatic diffuse large B-cell lymphoma (DLBCL). Similarly, Helicobacter pylori has been associated with gastric DLBCL.

Staging and Workup

A tissue biopsy is essential in the diagnosis and management of NHL. The most significant disadvantage of fine-needle aspiration cytology is the lack of histologic architecture. The optimal specimen is an excisional biopsy; when this cannot be performed, a core needle biopsy, ideally using a 16-gauge or larger caliber needle, is the next best choice.

The baseline tests appropriate for most cases of newly diagnosed aggressive B-cell NHL are listed in Table 1. 

Prior to the initiation of treatment, patients should always undergo a thorough cardiac and pulmonary evaluation, especially if the patient will be treated with an anthracycline or mediastinal irradiation. Central nervous system (CNS) evaluation with magnetic resonance imaging (MRI) and lumbar puncture is essential if there are neurological signs or symptoms. In addition, certain anatomical sites including the testicles, paranasal sinuses, kidney, adrenal glands, and epidural space have been associated with increased involvement of the CNS and may warrant MRI evaluation and lumbar puncture. Certain NHL subtypes like Burkitt lymphoma, high-grade NHL with translocations of MYC and BCL-2 or BCL-6 (double-hit lymphoma), blastoid mantle cell lymphoma, and lymphoblastic lymphoma have a high risk of CNS involvement, and patients with these subtypes need CNS evaluation.

The Lugano classification is used to stage patients with NHL [14]. This classification is based on the Ann Arbor staging system and uses the distribution and number of tumor sites to stage disease. In general, this staging system in isolation is of limited value in predicting survival after treatment. However, the Ann Arbor stage does have prognostic impact when incorporated into risk scoring systems such as the International Prognostic Index (IPI). In clinical practice, the Ann Arbor stage is useful primarily to determine eligibility for localized therapy approaches. The absence or presence of systemic symptoms such as fevers, drenching night sweats, or weight loss (> 10% of baseline over 6 months or less) is designated by A or B, respectively.

Diffuse Large B-Cell Lymphoma

DLBCL is the most common lymphoid neoplasm in adults, accounting for about 25% of all NHL cases [2]. It is increasingly clear that the diagnostic category of DLBCL is quite heterogeneous in terms of morphology, genetics, and biologic behavior. A number of clinicopathologic subtypes of DLBCL exist, such as T cell/histiocyte–rich large B-cell lymphoma, primary mediastinal large B-cell lymphoma, intravascular large B-cell lymphoma, DLBCL associated with chronic inflammation, lymphomatoid granulomatosis, and EBV-positive large B-cell lymphoma, among others. Gene expression profiling (GEP) can distinguish 2 cell of origin DLBCL subtypes: the germinal center B-cell (GCB) and activated B-cell (ABC) subtypes [15].

DLBCL may be primary (de novo) or may arise through the transformation of many different types of low-grade B-cell lymphomas. This latter scenario is referred to as histologic transformation or transformed lymphoma. In some cases, patients may have a previously diagnosed low-grade B-cell NHL; in other cases, both low-grade and aggressive B-cell NHL may be diagnosed concurrently. The presence of elements of both low-grade and aggressive B-cell NHL in the same biopsy specimen is sometimes referred to as a composite lymphoma.

In the United States, incidence varies by ethnicity, with DLBCL being more common in Caucasians than other races [16]. There is a slight male predominance (55%), median age at diagnosis is 65 years [16,17] and the incidence increases with age.

Presentation, Pathology, and Prognostic Factors

The most common presentation of patients with DLBCL is rapidly enlarging lymphadenopathy, usually in the neck or abdomen. Extranodal/extramedullary presentation is seen in approximately 40% of cases, with the gastrointestinal (GI) tract being the most common site. However, extranodal DLBCL can arise in virtually any tissue [18]. Nodal DLBCL presents with symptoms related to the sites of involvement (eg, shortness of breath or chest pain with mediastinal lymphadenopathy), while extranodal DLBCL typically presents with symptoms secondary to dysfunction at the site of origin. Up to one third of patients present with constitutional symptoms (B symptoms) and more than 50% have elevated serum lactate dehydrogenase (LDH) at diagnosis [19].

Approximately 40% of patients present with stage I/II disease. Of these, only a subset present with stage I, or truly localized disease (defined as that which can be contained within 1 irradiation field). About 60% of patients present with advanced (stage III–IV) disease [20]. The bone marrow is involved in about 15% to 30% of cases. DLBCL involvement of the bone marrow is associated with a less favorable prognosis. Patients with DLBCL elsewhere may have low-grade NHL involvement of the bone marrow. Referred to as discordant bone marrow involvement [21], this feature does not carry the same poor prognosis associated with transformed disease [22] or DLBCL involvement of the bone marrow [23].

DLBCL is defined as a neoplasm of large B-lymphoid cells with a diffuse growth pattern. The proliferative fraction of cells, as determined by Ki-67 staining, is usually greater than 40%, and may even exceed 90%. Lymph nodes usually demonstrate complete effacement of the normal architecture by sheets of atypical lymphoid cells. Tumor cells in DLBCL generally express pan B-cell antigens (CD19, CD20, CD22, CD79a, Pax-5) as well as CD45 and surface immunoglobulin. Between 20% and 37% of DLBCL cases express the BCL-2 protein [24], and about 70% express the BCL-6 protein [25]. C-MYC protein expression is seen in a higher percentage (~ 30%–50%) of cases of DLBCL [26].

Many factors are associated with outcome in DLBCL. The IPI score was developed in the pre-rituximab era and is a robust prognostic tool. This simple tool uses 5 easily obtained clinical factors (age > 60 years, impaired performance status, elevated LDH, > 1 extranodal site of disease, and stage III/IV disease). By summing these factors, 4 groups with distinct 5-year overall survival (OS) rates ranging from 26% to 73% were identified (Table 2). 

Cytogenetic and molecular factors also predict outcome in DLBCL. The ABC subtype distinguished by GEP has consistently been shown to have inferior outcomes with first-line therapy. As GEP is not routinely available in clinical practice, immunohistochemical (IHC) approaches (eg, the Hans algorithm) have been developed that can approximate the GEP subtypes. These IHC approaches have approximately 80% concordance with GEP [28]. The 3 most common chromosomal translocations in DLBCL involve BCL-2, BCL-6 and MYC. MYC-rearranged DLBCLs have a less favorable prognosis [29,30]. Cases in which a MYC translocation occurs in combination with a BCL-2 or BCL-6 translocation are commonly referred to as double-hit lymphoma (DHL); cases with all 3 translocations are referred to as triple-hit lymphoma (THL). Both DHL and THL have a worse prognosis with standard DLBCL therapy compared to non-DHL/THL cases. In the 2016 revised WHO classification, DHL and THL are an entity technically distinct from DLBCL, referred to as high-grade B-cell lymphoma [1]. In some cases, MYC and BCL-2 protein overexpression occurs in the absence of chromosomal translocations. Cases in which MYC and BCL-2 are overexpressed (by IHC) are referred to as double expressor lymphoma (DEL), and also have inferior outcome compared with non-DEL DLBCL [31,32]. Interestingly, MYC protein expression alone does not confer inferior outcomes, unlike isolated MYC translocation, which is associated with inferior outcomes.

Treatment

First-Line Therapy. DLBCL is an aggressive disease and, in most cases, survival without treatment can be measured in weeks to months. The advent of combination chemotherapy (CHOP [cyclophosphamide, doxorubicin, vincristine, and prednisone] or CHOP-like regimens) led to disease-free survival (DFS) rates of 35% to 40% at 3 to 5 years [33]. The addition of rituximab to CHOP (R-CHOP) has improved both progression-free surivial (PFS) and OS [34,35].

Treatment options vary for patients with localized (stage I/II) and advanced (stage III/IV) disease. Options for limited-stage DLBCL include an abbreviated course of R-CHOP (3 or 4 cycles) with involved-field radiation therapy (IFRT) versus a full course (6–8 cycles) of R-CHOP without radiation therapy (RT). Most studies comparing combined modality therapy (chemotherapy plus RT) versus chemotherapy alone were conducted in the pre-rituximab era. With the introduction of rituximab, Persky and colleagues [36] studied the use of 3 cycles of R-CHOP followed by RT, demonstrating a slightly improved OS of 92% at 4 years as compared to 88% in a historical cohort. The French LYSA/GOELAMS group performed the only direct comparison in the rituximab era (4 cycles of R-CHOP followed by RT versus 4 cycles of R-CHOP followed by 2 additional cycles of R-CHOP) and reported similar outcomes between both arms [37], with OS of 92% in the R-CHOP alone arm and 96% in the R-CHOP + RT arm (nonsignificant difference statistically). IFRT alone is not recommended other than for palliation in patients who cannot tolerate chemotherapy or combined modality therapy. Stage I and II patients with bulky disease (> 10 cm) have a prognosis similar to patients with advanced DLBCL and should be treated aggressively with 6 to 8 cycles of R-CHOP with or without RT [36].

For patients with advanced stage disease, a full course of R-CHOP-21 (6–8 cycles given on a 21-day cycle) is the standard of care. This approach results in OS rates of 70% and 60% at 2 and 5 years, respectively. For older adults unable to tolerate full-dose R-CHOP, attenuated versions of R-CHOP with decreased dose density or decreased dose intensity have been developed [38]. Numerous randomized trials have attempted to improve upon the results of R-CHOP-21 using strategies such as infusional chemotherapy (DA-EPOCH-R [etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, rituximab]) [39]; dose-dense therapy (R-CHOP-14); replacement of rituximab with obinutuzuimab [40]; addition of novel agents such as bortezomib [41], lenalidomide[42], or ibrutinib [43,44] to R-CHOP; and various maintenance strategies such as rituximab, lenalidomide [45], enzastaurin [46], and everolimus [47]. Unfortunately, none of these strategies has been shown to improve OS in DLBCL. In part this appears to be due to the fact that inclusion/exclusion criteria for DLBCL trials have been too strict, such that the most severely ill DLBCL patients are typically not included. As a result, the results in the control arms have ended up better than what was expected based on historical data. Efforts are underway to include all patients in future first-line DLBCL studies.

Currently, autologous hematopoietic cell transplantation (auto-HCT) is not routinely used in the initial treatment of DLBCL. In the pre-rituximab era, numerous trials were conducted in DLBCL patients with high and/or high-intermediate risk disease based on the IPI score to determine if outcomes could be improved with high-dose therapy and auto-HCT as consolidation after patients achieved complete remission with first-line therapy. The results of these trials were conflicting. A 2003 meta-analysis of 11 such trials concluded that the results were very heterogeneous and showed no OS benefit [48]. More recently, the Southwestern Oncology Group published the results of a prospective trial testing the impact of auto-HCT for consolidation of aggressive NHL patients with an IPI score of 3 to 5 who achieved complete remission with first-line therapy with CHOP or R-CHOP. In this study, 75% of the patients had DLBCL and, of the B-cell NHL patients, 47% received R-CHOP. A survival benefit was seen only in the subgroup that had an IPI score of 4 or 5; a subgroup analysis restricted to those receiving R-CHOP as induction was not performed, however [49]. As a result, this area remains controversial, with most institutions not routinely performing auto-HCT for any DLBCL patients in first complete remission and some institutions considering auto-HCT in first complete remission for patients with an IPI score of 4 or 5. These studies all used the IPI score to identify high-risk patients. It is possible that the use of newer biomarkers or minimal-residual disease analysis will lead to a more robust algorithm for identifying high-risk patients and selecting patients who might benefit from consolidation of first complete remission with auto-HCT.

For patients with DHL or THL, long-term PFS with standard R-CHOP therapy is poor (20% to 40%) [50,51]. Treatment with more intensive first-line regimens such as DA-EPOCH-R, R-hyperCVAD (rituximab plus hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone), or CODOX-M/IVAC±R (cyclophosphamide, vincristine, doxorubicin, high‐dose methotrexate/ifosfamide, etoposide, high‐dose cytarabine ± rituximab), along with CNS prophylaxis, however, has been shown to produce superior outcomes [52], with 3-year relapse-free survival rates of 88% compared to 56% for R-CHOP. For patients who achieve a complete response by PET/CT scan after intensive induction, consolidation with auto-HCT has not been shown to improve outcomes based on retrospective analysis. However for DHL/THL patients who achieve complete response after R-CHOP, PFS was improved if auto-HCT was given as consolidation of first remission [53].

Patients with DLBCL have an approximately 5% risk of subsequently developing CNS involvement. Historically (in the pre-rituximab era), patients who presented with multiple sites of extranodal disease and/or extensive bone marrow involvement and/or an elevated LDH had an increased risk (up to 20%–30%) of developing CNS involvement. In addition, patients with involvement of certain anatomical sites (testicular, paranasal sinuses, epidural space) had an increased risk of CNS disease. Several algorithms have been proposed to identify patients who should receive prophylactic CNS therapy. One of the most robust tools for this purpose is the CNS-IPI, which is a 6-point score consisting of the 5 IPI elements, plus 1 additional point if the adrenal glands or kidneys are involved. Importantly, the CNS-IPI was developed and validated in patients treated with R-CHOP-like therapy. Subsequent risk of CNS relapse was 0.6%, 3.4%, and 10.2% for those with low-, intermediate- and high-risk CNS-IPI scores, respectively [54]. A reasonable strategy, therefore, is to perform CNS prophylaxis in those with a CNS-IPI score of 4 to 6. When CNS prophylaxis is used, intrathecal methotrexate or high-dose systemic methotrexate is most frequently given, with high-dose systemic methotrexate favored over intrathecal chemotherapy given that high-dose methotrexate penetrates the brain and spinal cord parenchyma, in addition to treating the cerebrospinal fluid (CSF) [55]. In contrast, intrathecal therapy only treats the CSF and requires repeated lumbar punctures or placement of an Ommaya reservoir. For DLBCL patients who present with active CSF involvement (known as lymphomatous meningitis), intrathecal chemotherapy treatments are typically given 2 or 3 times weekly until the CSF clears, followed by weekly intrathecal treatment for 4 weeks, and then monthly intrathecal treatment for 4 months [56]. For those with concurrent systemic and brain parenchymal DLBCL, a strategy of alternating R-CHOP with mid-cycle high-dose methotrexate can be successful. In addition, consolidation with high-dose therapy and auto-HCT improved survival in such patients in 1 retrospective series [57].

Relapsed/Refractory Disease. Between 30% and 40% of patients with advanced stage DLBCL will either fail to attain a remission with primary therapy (referred to as primary induction failure) or will relapse. In general, for those with progressive or relapsed disease, an updated tissue biopsy is recommended. This is especially true for patients who have had prior complete remission and have new lymph node enlargement, or those who have emergence of new sites of disease at the completion of first-line therapy.

Patients with relapsed disease are treated with systemic second-line platinum-based chemoimmunotherapy, with the usual goal of ultimately proceeding to auto-HCT. A number of platinum-based regimens have been used in this setting such as R-ICE, R-DHAP, R-GDP, R-Gem-Ox, and R-ESHAP. None of these regimens has been shown to be superior in terms of efficacy, and the choice of regimen is typically made based on the anticipated tolerance of the patient in light of comorbidities, laboratory studies, and physician preference. In the CORAL study, R-DHAP (rituximab, dexamethasone, high-dose cytarabine, cisplatin) seemed to show superior PFS in patients with the GCB subtype [58]. However, this was an unplanned subgroup analysis and R-DHAP was associated with higher renal toxicity.

Several studies have demonstrated that long-term PFS can be observed for relapsed/refractory DLBCL patients who respond to second-line therapy and then undergo high-dose therapy with auto-HCT. The Parma trial remains the only published prospective randomized trial performed in relapsed DLBCL comparing a transplant strategy to a non-transplant strategy. This study, performed in the pre-rituximab era, clearly showed a benefit in terms of DFS and OS in favor of auto-HCT versus salvage therapy alone [59]. The benefit of auto-HCT in patients treated in the rituximab era, even in patients who experience early failure (within 1 year of diagnosis), was confirmed in a retrospective analysis by the Center for International Blood and Marrow Transplant Research. In this study, a 44% 3-year PFS was seen in the early failure cohort versus 52% in the late failure cohort [60].

Some DLBCL patients are very unlikely to benefit from auto-HCT. The REFINE study focused on patients with primary induction failure or early relapse within 6 months of completing first-line therapy. Among such patients, primary progressive disease (defined as progression while still receiving first-line therapy), a high NCCN-IPI score at relapse, and MYC rearrangement were risk factors for poor PFS following auto-HCT [61]. Patients with 2 or 3 high-risk features had a 2-year OS of 10.7% compared to 74.3% for those without any high-risk features.

Allogeneic HCT (allo-HCT) is a treatment option for relapsed/refractory DLBCL. This option is more commonly considered for patients in whom an autotransplant has failed to achieve durable remission. For properly selected patients in this setting, a long-term PFS in the 30% to 40% range can be attained [62]. However, in practice, only about 20% of patients who fail auto-HCT end up undergoing allo-HCT due to rapid progression of disease, age, poor performance status, or lack of suitable donor. It has been proposed that in the coming years, allo-HCT will be utilized less commonly in this setting due to the advent of chimeric antigen receptor T-cell (CAR T) therapy.

CAR T-cell therapy genetically modifies the patient’s own T lymphocytes with a gene that encodes an antigen receptor to direct the T cells against lymphoma cells. Typically, the T cells are genetically modified and expanded in a production facility and then infused back into the patient. Axicabtagene ciloleucel is directed against the CD-19 receptor and has been approved by the US Food and Drug Administration (FDA) for treatment of patients with DLBCL who have failed 2 or more lines of systemic therapy. Use of CAR-T therapy in such patients was examined in a multicenter trial (ZUMA-1), which reported a 54% complete response rate and 52% OS rate at 18 months.63 CAR-T therapy is associated with serious side effects such as cytokine release syndrome, neurological toxicities, and prolonged cytopenias. While there are now some patients with ongoing remission 2 or more years after undergoing CAR-T therapy, it remains uncertain what proportion of patients have been truly cured with this modality. Nevertheless, this new treatment option remains a source of optimism for relapsed and refractory DLBCL patients.

Primary Mediastinal Large B-Cell Lymphoma

Primary mediastinal large B-cell lymphoma (PMBCL) is a form of DLBCL arising in the mediastinum from the thymic B cell. It is an uncommon entity and has clinical and pathologic features distinct from systemic DLBCL [64]. PMBCL accounts for 2% of all NHLs and about 7% of all DLBCL [20]. It typically affects women in the third to fourth decade of life.

Presentation and Prognostic Features

PMBCL usually presents as a locally invasive anterior mediastinal mass, often with a superior vena cava syndrome which may or may not be clinically obvious [64]. Other presentations include pericardial tamponade, thrombosis of neck veins, and acute airway obstruction. About 80% of patients present with bulky (> 10 cm) stage I or II disease [65], with distant spread uncommon on presentation. Morphologically and on GEP, PMBL has a profile more similar to classical Hodgkin lymphoma (cHL) than non-mediastinal DLBCL [66]. PMBL is distinguished from cHL by immunophenotyping: unlike cHL, PMBCL has pan B cell markers, rarely expresses CD15, and has weak CD30.

Poor prognostic features in PMBCL are Eastern Cooperative Oncology Group (ECOG) performance status greater than 2, pericardial effusion, bulky disease, and elevated serum LDH. The diagnosis of PMBCL can be difficult because the tumor is often encased with extensive fibrosis and necrosis. As a result, a needle biopsy may not yield sufficient tissue, thus making a surgical biopsy often the only viable way to obtain sufficient tissue.

Treatment

Early series suggested that PMBCL is unusually aggressive, with a poor prognosis [67]. This led to studies using more aggressive chemotherapy regimens (often in combination with mediastinal radiation) as well as upfront auto-HCT [68–70]. The addition of rituximab to treatment regimens significantly improved outcomes in PMBCL. For example, a subgroup analysis of the PMBCL patients in the MinT trial revealed a 3-year event-free survival (EFS) of 78% [71] when rituximab was combined with CHOP. Because of previous reports demonstrating radiosensitivity of PMBL, radiation was traditionally sequenced into treatment regimens for PMBL. However, this is associated with higher long-term toxicities, often a concern in PMBCL patients given that the disease frequently affects younger females, and given that breast tissue will be in the radiation field. For patients with a strong personal or family history of breast cancer or cardiovascular disease, these concerns are even more significant. More recently, the DA-EPOCH-R regimen has been shown to produce very high rates (80%–90%) of long-term DFS, without the need for mediastinal radiation in most cases [72,73]. For patients receiving R-CHOP, consolidation with mediastinal radiation is still commonly given. This approach also leads to high rates of long-term remission and, although utilizing mediastinal radiation, allows for less intensive chemotherapy. Determining which approach is most appropriate for an individual patient requires an assessment of the risks of each treatment option for that patient. A randomized trial by the International Extranodal Lymphoma Study Group (IELSG37) is evaluating whether RT may be safely omitted in PMBCL patients who achieve a complete metabolic response after R-CHOP.

Most relapses of PMBCL occur within the first 1 to 2 years and often present with extranodal disease in various organs. For those with relapsed or refractory disease, high-dose chemotherapy followed by auto-HCT provides 5-year survival rates of 50% to 80% [74–76] In a phase 1b trial evaluating the role of pembrolizumab in relapsed/refractory patients (KEYNOTE-13), 7 of 17 PMBCL patients achieved responses, with an additional 6 demonstrating stable disease [77]. This provides an additional option for patients who might be too weak to undergo auto-HCT or for those who relapse following auto-HCT.

Mantle Cell Lymphoma

The name mantle cell lymphoma (MCL) is based on the presumed normal cell counterpart to MCL, which is believed to be found in the mantle zone surrounding germinal center follicles. It represents approximately 6% of all NHL cases in the United States and Europe [78] MCL occurs at a median age of 63 to 68 years and has a male predominance.

Presentation and Prognostic Features

Patients can present with a broad spectrum of clinical features, and most patients (70%) present with advanced disease [79]. Up to one third of patients have B symptoms, with most demonstrating lymphadenopathy and bone marrow involvement. Approximately 25% present with extranodal disease as the primary presentation (eg, GI tract, pleura, breast, or orbits). MCL can involve any part of the GI tract and often presents as polypoid lesions.

Histologically, the pattern of MCL may be diffuse, nodular, mantle zone, or a combination of the these; morphologically, MCL can range from small, more irregular lymphocytes to lymphoblast-like cells. Blastoid and pleomorphic variants of MCL have a higher proliferation index and a more aggressive clinical course than other variants. MCL is characterized by the expression of pan B cell antigens (CD19+, CD20+) with coexpression of the T-cell antigen CD5, lack of CD23 expression, and nuclear expression of cyclin D1. Nuclear staining for cyclin D1 is present in more than 98% of cases [80]. In rare cases, CD5 or cyclin D1 may be negative [80]. Most MCL cases have a unique translocation that fuses the immunoglobulin heavy chain gene promoter (14q32) to the promoter of the BCL-1 gene (11q13), which encodes the cyclin D1 protein. This translocation is not unique to MCL and can be present in multiple myeloma as well. Interestingly, cyclin D1 is overproduced in cases lacking t(11:14), likely from other point mutations resulting in its overexpression [81]. Cyclin D1–negative tumors overexpress cyclin D2 or D3, with no apparent difference in clinical behavior or outcome [82]. In cyclin D1–negative cases, SOX11 expression may help with diagnosis [83]. A proliferation rate greater than 30% (as measured by Ki-67 staining), low SOX11 expression, and presence of p53 mutations have all been associated with adverse outcome.

In a minority of cases, MCL follows an indolent clinical course. For the remainder, however, MCL is an aggressive disease that generally requires treatment soon after diagnosis. When initially described in the 1980s and 1990s, treatment of MCL was characterized by low complete response rates, short durations of remission, repeated recurrences, and a median survival in the 2- to 5-year range [84]. In recent years, intensive regimens incorporating rituximab and high-dose cytarabine with or without auto-HCT have been developed and are associated with high complete response rates and median duration of first remission in the 6- to 9-year range [85–87]. Several prognostic indices have been applied to patients with MCL, including the IPI, the Follicular Lymphoma International Prognostic Index , and the Mantle Cell Lymphoma International Prognostic Index (MIPI). The MIPI was originally described based on a cohort from the period 1996 to 2004 [88], and subsequently confirmed in a separate cohort of 958 patients with MCL treated on prospective trials between 2004 and 2010 [89]. The MIPI score can identify 3 risk groups with significant survival differences (83%, 63%, and 34% survival at 5 years). A refined version of the MIPI score, the combined MIPI or MIPI-c, incorporates proliferation rate and is better able to stratify patients [90]. The blastoid variant of MCL follows a more aggressive clinical course and is associated with a high proliferation rate, shorter remissions, and a higher rate of CNS involvement [91].

In most patients, MCL is an aggressive disease with a short OS without treatment. A subset of patients may have a more indolent course [92], but unfortunately reliable factors that identify this group at the time of diagnosis are not available. Pretreatment evaluation is as with other lymphomas, with lumbar puncture and MRI of the brain also recommended for patients with the blastoid variant. For those presenting with GI symptoms, endoscopy is recommended as part of the initial evaluation as well.

Treatment

First-line Therapy. For patients under age 65 to 70 years with a good performance status and few comorbidities, an intensive induction regimen (such as R-CHOP/R-DHAP, Maxi-R-CHOP/R-araC, or R-DHAP) followed by consolidation with auto-HCT is commonly given, with a goal of achieving a durable (6–9 year) first remission [87,93,94]. Auto-HCT is now routinely followed by 3 years of maintenance rituximab based on the survival benefit seen in the recent LYSA trial [93]. At many centers, auto-HCT in first remission is a standard of care, with the greatest benefit seen in patients who have achieved a complete remission with no more than 2 lines of chemotherapy [95]. However, there remains some controversy about whether all patients truly benefit from auto-HCT in first remission, and current research efforts are focused on identifying patients most likely to benefit from auto-HCT and incorporation of new agents into first-line regimens. For patients who are not candidates for auto-HCT, bendamustine plus rituximab (BR) or R-CHOP alone or followed by maintenance rituximab is a reasonable approach [96]. Based on the StiL and BRIGHT trials, BR seems to have less toxicity and higher rates of response with no difference in OS when compared to R-CHOP [97,98].

In summary, dose-intense induction chemotherapy with consolidative auto-HCT results in high rates of long-term remission and can be considered in MCL patients who lack significant comorbidities and who understand the risks and benefits of this approach. For other patients, the less aggressive frontline approaches are more appropriate.

Relapsed/Refractory Disease

Despite initial high response rates, most patients with MCL will eventually relapse. For example, most patients given CHOP or R-CHOP alone as first-line therapy will relapse within 2 years [99]. In recent years, a number of therapies have emerged for relapsed/refractory MCL; however, the optimal sequencing of these is unclear. FDA-approved options for relapsed/refractory MCL include the proteasome inhibitor bortezomib [100,101], the BTK inhibitors ibrutinib [102,103] and acalabrutinib [104], and the immunomodulatory agent lenalidomide [105].

Auto-HCT can be considered for patients who did not undergo auto-HCT as part of first-line therapy and who had a reasonably long first remission [95]. Allo-HCT has curative potential in MCL with good evidence of a graft-versus-lymphoma effect. With a matched related or matched unrelated donor, the chance for treatment-related mortality is 15% to 25% at 1 to 2 years, with a 50% to 60% chance for long-term PFS. However, given the risk of treatment-related mortality and graft-versus-host disease, this option is typically reserved for patients with early relapse after auto-HCT, multiple relapses, or relatively chemotherapy-unresponsive disease [95,106]. A number of clinical trials for relapsed/refractory MCL are ongoing, and participation in these is encouraged whenever possible.

Burkitt Lymphoma

Burkitt lymphoma is a rare, aggressive and highly curable subtype of NHL. It can occur at any age, although peak incidence is in the first decade of life. There are 3 distinct clinical forms of Burkitt lymphoma [107]. The endemic form is common in African children and commonly involves the jaw and kidneys. The sporadic (nonendemic) form accounts for 1% to 2% of all lymphomas in the United States and Western Europe and usually has an abdominal presentation. The immunodeficiency-associated form is commonly seen in HIV patients with a relatively preserved CD4 cell count.

Patients typically present with rapidly growing masses and tumor lysis syndrome. CNS and bone marrow involvement are common. Burkitt lymphoma cells are high-grade, rapidly proliferating medium-sized cells with a monomorphic appearance. Biopsies show a classic histological appearance known as a “starry sky pattern” due to benign macrophages engulfing debris resulting from apoptosis. It is derived from a germinal center B cell and has distinct oncogenic pathways. Translocations such as t(8;14), t(2;8) or t(8;22) juxtapose the MYC locus with immunoglobulin heavy or light chain loci and result in MYC overexpression. Burkitt lymphoma is typically CD10-positive and BCL-2-negative, with a MYC translocation and a proliferation rate greater than 95%.

With conventional NHL regimens, Burkitt lymphoma had a poor prognosis, with complete remission in the 30% to 70% range and low rates of long-term remission. With the introduction of short-term, dose-intensive, multiagent chemotherapy regimens (adapted from pediatric acute lymphoblastic leukemia [ALL] regimens), the complete remission rate improved to 60% to 90% [107]. Early stage disease (localized or completely resected intra-abdominal disease) can have complete remission rates of 100%, with 2- to 5-year freedom-from-progression rates of 95%. CNS prophylaxis, including high-dose methotrexate, high-dose cytarabine, and intrathecal chemotherapy, is a standard component of Burkitt lymphoma regimens (CNS relapse rates can reach 50% without prophylactic therapy). Crucially, relapse after 1 to 2 years is very rare following complete response to induction therapy. Classically, several intensive regimens have been used for Burkitt lymphoma. In recent years, the most commonly used regimens have been the modified Magrath regimen of R-CODOX-M/IVAC and R-hyperCVAD. DA-EPOCH-R has also been used, typically for older, more frail, or HIV-positive patients. However, at the American Society of Hematology 2017 annual meeting, results from the NCI 9177 trial were presented which validated, in a prospective multi-center fashion, the use of DA-EPOCH-R in all Burkitt lymphoma patients [108]. In NCI 9177, low-risk patients (defined as normal LDH, ECOG performance score 0 or 1, ≤ stage II, and no tumor lesion > 7 cm) received 2 cycles of DA-EPOCH-R without intrathecal therapy followed by PET. If interim PET was negative, low-risk patients then received 1 more cycle of DA-EPOCH-R. High-risk patients with negative brain MRI and CSF cytology/flow cytometry received 2 cycles of DA-EPOCH-R with intrathecal therapy (2 doses per cycle) followed by PET. Unless interim PET showed progression, high-risk patients received 4 additional cycles of DA-EPOCH-R including methotrexate 12 mg intrathecally on days 1 and 5 (8 total doses). With a median follow-up of 36 months, this regimen resulted in an EFS of 85.7%. As expected, patients with CNS, marrow, or peripheral blood involvement fared worse. For those without CNS, marrow, or peripheral blood involvement, the results were excellent, with an EFS of 94.6% compared to 62.8% for those with CNS, bone marrow, or blood involvement at diagnosis.

Although no standard of care has been defined, patients with relapsed/refractory Burkitt lymphoma are often given standard second-line aggressive NHL regimens (eg, R-ICE); for those with chemosensitive disease, auto- or allo-HCT is often pursued, with long-term remissions possible following HCT [109].

Lymphoblastic Lymphoma

Lymphoblastic lymphoma (LBL) is a rare disease postulated to arise from precursor B or T lymphoblasts at varying stages of differentiation. Accounting for approximately 2% of all NHLs, 85% to 90% of all cases have a T-cell phenotype, while B-cell LBL comprises approximately 10% to 15% of cases. LBL and ALL are thought to represent the same disease entity, but LBL has been arbitrarily defined as cases with lymph node or mediastinal disease. Those with significant (> 25%) bone marrow or peripheral blood involvement are classified as ALL.

Precursor T-cell LBL patients are usually adolescent and young males who commonly present with a mediastinal mass and peripheral lymphadenopathy. Precursor B-cell LBL patients are usually older (median age 39 years) with peripheral lymphadenopathy and extranodal involvement. Mediastinal involvement with B-cell LBL is uncommon, and there is no male predominance. LBL has a propensity for dissemination to the bone marrow and CNS.

Morphologically, the tumor cells are medium sized, with a scant cytoplasm and finely dispersed chromatin. Mitotic features and apoptotic bodies are present since it is a high-grade malignancy. The lymphoblasts are typically positive for CD7 and either surface or cytoplasmic CD3. Terminal deoxynucleotidyl transferase expression is a defining feature. Other markers such as CD19, CD22, CD20, CD79a, CD45, and CD10 are variably expressed. Poor prognostic factors in T-cell LBL are female gender, age greater than 35 years, complex cytogenetics, and lack of a matched sibling donor.

Regimens for LBL are based on dose-dense, multi-agent protocols used in ALL. Most of these regimens are characterized by intensive remission-induction chemotherapy, CNS prophylaxis, a phase of consolidation therapy, and a prolonged maintenance phase, often lasting for 12 to 18 months with long-term DFS rates of 40% to 70% [110,111]. High-dose therapy with auto-HCT or allo-HCT in first complete response has been evaluated in an attempt to reduce the incidence of relapse [112]. However, the intensity of primary chemotherapy appears to be a stronger determinant of long-term survival than the use of HCT as consolidation. As a result, HCT is not routinely applied to patients in first complete remission following modern induction regimens. After relapse, prognosis is poor, with median survival rates of 6 to 9 months with conventional chemotherapy, although long-term survival rates of 30% and 20%, respectively, are reported after HCT in relapsed and primary refractory disease [113].

Treatment options in relapsed disease are limited. Nelarabine can produce responses in up to 40% of relapsed/refractory LBL/ALL patients [114]. For the minority of LBL patients with a B-cell phenotype, emerging options for relapsed/refractory LBL/ALL such as inotuzumab, blinatumomab, or anti-CD19 CAR T-cell therapy should be considered. These are not options for the majority who have a T-cell phenotype, and treatment options for these patients are limited to conventional relapsed/refractory ALL and aggressive NHL regimens.

Summary

Aggressive NHLs are characterized by rapid clinical progression without therapy. However, a significant proportion of patients are cured with appropriate combination chemotherapy or combined modality (chemotherapy + RT) regimens. In contrast, the indolent lymphomas have a relatively good prognosis (median survival of 10 years or longer) but usually are not curable in advanced clinical stages. Overall 5-year survival for aggressive NHLs with current treatment is approximately 50% to 60%, with relapses typically occurring within the first 5 years. Treatment strategies for relapsed patients offer some potential for cure; however, clinical trial participation should be encouraged whenever possible to investigate new approaches for improving outcomes in this patient population.

Corresponding author: Timothy S. Fenske, MD, Division of Hematology & Oncology, Medical College of Wisconsin, 9200 W. Wisconsin Ave., Milwaukee, WI 53226.

Abstract

• Objective: To review the diagnosis and management of aggressive B-cell non-Hodgkin lymphoma (NHL).
• Methods: Review of the literature.
• Results: NHL comprises a wide variety of malignant hematologic disorders with varying clinical and biological features. Aggressive NHLs are characterized by rapid clinical progression without therapy. However, a significant proportion of patients are cured with appropriate combination chemotherapy or combined modality regimens. In contrast, the indolent lymphomas have a relatively good prognosis (median survival of 10 years or longer) but usually are not curable in advanced clinical stages. Overall 5-year survival for aggressive NHLs with current treatment is approximately 50% to 60%, with relapses typically occurring within the first 5 years.
• Conclusion: Treatment strategies for relapsed patients offer some potential for cure; however, clinical trial participation should be encouraged whenever possible to investigate new approaches for improving outcomes in this patient population.

Non-Hodgkin lymphoma (NHL) comprises a wide variety of malignant hematologic disorders with varying clinical and biological features. The more than 60 separate NHL subtypes can be classified according to cell of origin (B cell versus T cell), anatomical location (eg, orbital, testicular, bone, central nervous system), clinical behavior (indolent versus aggressive), histological features, or cytogenetic abnormalities. Although various NHL classification schemes have been used over the years, the World Health Organization (WHO) classification is now widely accepted as the definitive pathologic classification system for lymphoproliferative disorders, incorporating morphologic, immunohistochemical, flow cytometric, cytogenetic, and molecular features [1]. While the pathologic and molecular subclassification of NHL has become increasingly refined in recent years, from a management standpoint, classification based on clinical behavior remains very useful. This approach separates NHL subtypes into indolent versus aggressive categories. Whereas indolent NHLs may remain clinically insignificant for months to years, aggressive B-cell NHLs generally become life-threatening within weeks to months without treatment.

Epidemiology

Data from cancer registries show a steady, unexplainable increase in the incidence of NHL during the second half of the 20th century; the incidence has subsequently plateaued. There was a significant increase in NHL incidence between 1970 and 1995, which has been attributed in part to the HIV epidemic. More than 72,000 new cases of NHL were diagnosed in the United States in 2017, compared to just over 8000 cases of Hodgkin lymphoma, making NHL the sixth most common cancer in adult men and the fifth most common in adult women [2]. NHL appears to occur more frequently in Western countries than in Asian populations.

Various factors associated with increased risk for B-cell NHL have been identified over the years, including occupational and environmental exposure to certain pesticides and herbicides [3], immunosuppression associated with HIV infection [4], autoimmune disorders [5], iatrogenically induced immune suppression in the post-transplant and other settings [6], family history of NHL [7], and a personal history of a prior cancer, including Hodgkin lymphoma and prior NHL [8]. In terms of infectious agents associated with aggressive B-cell NHLs, Epstein-Barr virus (EBV) has a clear pathogenic role in Burkitt lymphoma, in many cases of post-transplant lymphoproliferative disorders, and in some cases of HIV-related aggressive B-cell lymphoma [9]. Human herpesvirus-8 viral genomes have been found in virtually all cases of primary effusion lymphomas [10]. Epidemiological studies also have linked hepatitis B and C to increased incidences of certain NHL subtypes [11–13], including primary hepatic diffuse large B-cell lymphoma (DLBCL). Similarly, Helicobacter pylori has been associated with gastric DLBCL.

Staging and Workup

A tissue biopsy is essential in the diagnosis and management of NHL. The most significant disadvantage of fine-needle aspiration cytology is the lack of histologic architecture. The optimal specimen is an excisional biopsy; when this cannot be performed, a core needle biopsy, ideally using a 16-gauge or larger caliber needle, is the next best choice.

The baseline tests appropriate for most cases of newly diagnosed aggressive B-cell NHL are listed in Table 1. 

Prior to the initiation of treatment, patients should always undergo a thorough cardiac and pulmonary evaluation, especially if the patient will be treated with an anthracycline or mediastinal irradiation. Central nervous system (CNS) evaluation with magnetic resonance imaging (MRI) and lumbar puncture is essential if there are neurological signs or symptoms. In addition, certain anatomical sites including the testicles, paranasal sinuses, kidney, adrenal glands, and epidural space have been associated with increased involvement of the CNS and may warrant MRI evaluation and lumbar puncture. Certain NHL subtypes like Burkitt lymphoma, high-grade NHL with translocations of MYC and BCL-2 or BCL-6 (double-hit lymphoma), blastoid mantle cell lymphoma, and lymphoblastic lymphoma have a high risk of CNS involvement, and patients with these subtypes need CNS evaluation.

The Lugano classification is used to stage patients with NHL [14]. This classification is based on the Ann Arbor staging system and uses the distribution and number of tumor sites to stage disease. In general, this staging system in isolation is of limited value in predicting survival after treatment. However, the Ann Arbor stage does have prognostic impact when incorporated into risk scoring systems such as the International Prognostic Index (IPI). In clinical practice, the Ann Arbor stage is useful primarily to determine eligibility for localized therapy approaches. The absence or presence of systemic symptoms such as fevers, drenching night sweats, or weight loss (> 10% of baseline over 6 months or less) is designated by A or B, respectively.

Diffuse Large B-Cell Lymphoma

DLBCL is the most common lymphoid neoplasm in adults, accounting for about 25% of all NHL cases [2]. It is increasingly clear that the diagnostic category of DLBCL is quite heterogeneous in terms of morphology, genetics, and biologic behavior. A number of clinicopathologic subtypes of DLBCL exist, such as T cell/histiocyte–rich large B-cell lymphoma, primary mediastinal large B-cell lymphoma, intravascular large B-cell lymphoma, DLBCL associated with chronic inflammation, lymphomatoid granulomatosis, and EBV-positive large B-cell lymphoma, among others. Gene expression profiling (GEP) can distinguish 2 cell of origin DLBCL subtypes: the germinal center B-cell (GCB) and activated B-cell (ABC) subtypes [15].

DLBCL may be primary (de novo) or may arise through the transformation of many different types of low-grade B-cell lymphomas. This latter scenario is referred to as histologic transformation or transformed lymphoma. In some cases, patients may have a previously diagnosed low-grade B-cell NHL; in other cases, both low-grade and aggressive B-cell NHL may be diagnosed concurrently. The presence of elements of both low-grade and aggressive B-cell NHL in the same biopsy specimen is sometimes referred to as a composite lymphoma.

In the United States, incidence varies by ethnicity, with DLBCL being more common in Caucasians than other races [16]. There is a slight male predominance (55%), median age at diagnosis is 65 years [16,17] and the incidence increases with age.

Presentation, Pathology, and Prognostic Factors

The most common presentation of patients with DLBCL is rapidly enlarging lymphadenopathy, usually in the neck or abdomen. Extranodal/extramedullary presentation is seen in approximately 40% of cases, with the gastrointestinal (GI) tract being the most common site. However, extranodal DLBCL can arise in virtually any tissue [18]. Nodal DLBCL presents with symptoms related to the sites of involvement (eg, shortness of breath or chest pain with mediastinal lymphadenopathy), while extranodal DLBCL typically presents with symptoms secondary to dysfunction at the site of origin. Up to one third of patients present with constitutional symptoms (B symptoms) and more than 50% have elevated serum lactate dehydrogenase (LDH) at diagnosis [19].

Approximately 40% of patients present with stage I/II disease. Of these, only a subset present with stage I, or truly localized disease (defined as that which can be contained within 1 irradiation field). About 60% of patients present with advanced (stage III–IV) disease [20]. The bone marrow is involved in about 15% to 30% of cases. DLBCL involvement of the bone marrow is associated with a less favorable prognosis. Patients with DLBCL elsewhere may have low-grade NHL involvement of the bone marrow. Referred to as discordant bone marrow involvement [21], this feature does not carry the same poor prognosis associated with transformed disease [22] or DLBCL involvement of the bone marrow [23].

DLBCL is defined as a neoplasm of large B-lymphoid cells with a diffuse growth pattern. The proliferative fraction of cells, as determined by Ki-67 staining, is usually greater than 40%, and may even exceed 90%. Lymph nodes usually demonstrate complete effacement of the normal architecture by sheets of atypical lymphoid cells. Tumor cells in DLBCL generally express pan B-cell antigens (CD19, CD20, CD22, CD79a, Pax-5) as well as CD45 and surface immunoglobulin. Between 20% and 37% of DLBCL cases express the BCL-2 protein [24], and about 70% express the BCL-6 protein [25]. C-MYC protein expression is seen in a higher percentage (~ 30%–50%) of cases of DLBCL [26].

Many factors are associated with outcome in DLBCL. The IPI score was developed in the pre-rituximab era and is a robust prognostic tool. This simple tool uses 5 easily obtained clinical factors (age > 60 years, impaired performance status, elevated LDH, > 1 extranodal site of disease, and stage III/IV disease). By summing these factors, 4 groups with distinct 5-year overall survival (OS) rates ranging from 26% to 73% were identified (Table 2). 

Cytogenetic and molecular factors also predict outcome in DLBCL. The ABC subtype distinguished by GEP has consistently been shown to have inferior outcomes with first-line therapy. As GEP is not routinely available in clinical practice, immunohistochemical (IHC) approaches (eg, the Hans algorithm) have been developed that can approximate the GEP subtypes. These IHC approaches have approximately 80% concordance with GEP [28]. The 3 most common chromosomal translocations in DLBCL involve BCL-2, BCL-6 and MYC. MYC-rearranged DLBCLs have a less favorable prognosis [29,30]. Cases in which a MYC translocation occurs in combination with a BCL-2 or BCL-6 translocation are commonly referred to as double-hit lymphoma (DHL); cases with all 3 translocations are referred to as triple-hit lymphoma (THL). Both DHL and THL have a worse prognosis with standard DLBCL therapy compared to non-DHL/THL cases. In the 2016 revised WHO classification, DHL and THL are an entity technically distinct from DLBCL, referred to as high-grade B-cell lymphoma [1]. In some cases, MYC and BCL-2 protein overexpression occurs in the absence of chromosomal translocations. Cases in which MYC and BCL-2 are overexpressed (by IHC) are referred to as double expressor lymphoma (DEL), and also have inferior outcome compared with non-DEL DLBCL [31,32]. Interestingly, MYC protein expression alone does not confer inferior outcomes, unlike isolated MYC translocation, which is associated with inferior outcomes.

Treatment

First-Line Therapy. DLBCL is an aggressive disease and, in most cases, survival without treatment can be measured in weeks to months. The advent of combination chemotherapy (CHOP [cyclophosphamide, doxorubicin, vincristine, and prednisone] or CHOP-like regimens) led to disease-free survival (DFS) rates of 35% to 40% at 3 to 5 years [33]. The addition of rituximab to CHOP (R-CHOP) has improved both progression-free surivial (PFS) and OS [34,35].

Treatment options vary for patients with localized (stage I/II) and advanced (stage III/IV) disease. Options for limited-stage DLBCL include an abbreviated course of R-CHOP (3 or 4 cycles) with involved-field radiation therapy (IFRT) versus a full course (6–8 cycles) of R-CHOP without radiation therapy (RT). Most studies comparing combined modality therapy (chemotherapy plus RT) versus chemotherapy alone were conducted in the pre-rituximab era. With the introduction of rituximab, Persky and colleagues [36] studied the use of 3 cycles of R-CHOP followed by RT, demonstrating a slightly improved OS of 92% at 4 years as compared to 88% in a historical cohort. The French LYSA/GOELAMS group performed the only direct comparison in the rituximab era (4 cycles of R-CHOP followed by RT versus 4 cycles of R-CHOP followed by 2 additional cycles of R-CHOP) and reported similar outcomes between both arms [37], with OS of 92% in the R-CHOP alone arm and 96% in the R-CHOP + RT arm (nonsignificant difference statistically). IFRT alone is not recommended other than for palliation in patients who cannot tolerate chemotherapy or combined modality therapy. Stage I and II patients with bulky disease (> 10 cm) have a prognosis similar to patients with advanced DLBCL and should be treated aggressively with 6 to 8 cycles of R-CHOP with or without RT [36].

For patients with advanced stage disease, a full course of R-CHOP-21 (6–8 cycles given on a 21-day cycle) is the standard of care. This approach results in OS rates of 70% and 60% at 2 and 5 years, respectively. For older adults unable to tolerate full-dose R-CHOP, attenuated versions of R-CHOP with decreased dose density or decreased dose intensity have been developed [38]. Numerous randomized trials have attempted to improve upon the results of R-CHOP-21 using strategies such as infusional chemotherapy (DA-EPOCH-R [etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, rituximab]) [39]; dose-dense therapy (R-CHOP-14); replacement of rituximab with obinutuzuimab [40]; addition of novel agents such as bortezomib [41], lenalidomide[42], or ibrutinib [43,44] to R-CHOP; and various maintenance strategies such as rituximab, lenalidomide [45], enzastaurin [46], and everolimus [47]. Unfortunately, none of these strategies has been shown to improve OS in DLBCL. In part this appears to be due to the fact that inclusion/exclusion criteria for DLBCL trials have been too strict, such that the most severely ill DLBCL patients are typically not included. As a result, the results in the control arms have ended up better than what was expected based on historical data. Efforts are underway to include all patients in future first-line DLBCL studies.

Currently, autologous hematopoietic cell transplantation (auto-HCT) is not routinely used in the initial treatment of DLBCL. In the pre-rituximab era, numerous trials were conducted in DLBCL patients with high and/or high-intermediate risk disease based on the IPI score to determine if outcomes could be improved with high-dose therapy and auto-HCT as consolidation after patients achieved complete remission with first-line therapy. The results of these trials were conflicting. A 2003 meta-analysis of 11 such trials concluded that the results were very heterogeneous and showed no OS benefit [48]. More recently, the Southwestern Oncology Group published the results of a prospective trial testing the impact of auto-HCT for consolidation of aggressive NHL patients with an IPI score of 3 to 5 who achieved complete remission with first-line therapy with CHOP or R-CHOP. In this study, 75% of the patients had DLBCL and, of the B-cell NHL patients, 47% received R-CHOP. A survival benefit was seen only in the subgroup that had an IPI score of 4 or 5; a subgroup analysis restricted to those receiving R-CHOP as induction was not performed, however [49]. As a result, this area remains controversial, with most institutions not routinely performing auto-HCT for any DLBCL patients in first complete remission and some institutions considering auto-HCT in first complete remission for patients with an IPI score of 4 or 5. These studies all used the IPI score to identify high-risk patients. It is possible that the use of newer biomarkers or minimal-residual disease analysis will lead to a more robust algorithm for identifying high-risk patients and selecting patients who might benefit from consolidation of first complete remission with auto-HCT.

For patients with DHL or THL, long-term PFS with standard R-CHOP therapy is poor (20% to 40%) [50,51]. Treatment with more intensive first-line regimens such as DA-EPOCH-R, R-hyperCVAD (rituximab plus hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone), or CODOX-M/IVAC±R (cyclophosphamide, vincristine, doxorubicin, high‐dose methotrexate/ifosfamide, etoposide, high‐dose cytarabine ± rituximab), along with CNS prophylaxis, however, has been shown to produce superior outcomes [52], with 3-year relapse-free survival rates of 88% compared to 56% for R-CHOP. For patients who achieve a complete response by PET/CT scan after intensive induction, consolidation with auto-HCT has not been shown to improve outcomes based on retrospective analysis. However for DHL/THL patients who achieve complete response after R-CHOP, PFS was improved if auto-HCT was given as consolidation of first remission [53].

Patients with DLBCL have an approximately 5% risk of subsequently developing CNS involvement. Historically (in the pre-rituximab era), patients who presented with multiple sites of extranodal disease and/or extensive bone marrow involvement and/or an elevated LDH had an increased risk (up to 20%–30%) of developing CNS involvement. In addition, patients with involvement of certain anatomical sites (testicular, paranasal sinuses, epidural space) had an increased risk of CNS disease. Several algorithms have been proposed to identify patients who should receive prophylactic CNS therapy. One of the most robust tools for this purpose is the CNS-IPI, which is a 6-point score consisting of the 5 IPI elements, plus 1 additional point if the adrenal glands or kidneys are involved. Importantly, the CNS-IPI was developed and validated in patients treated with R-CHOP-like therapy. Subsequent risk of CNS relapse was 0.6%, 3.4%, and 10.2% for those with low-, intermediate- and high-risk CNS-IPI scores, respectively [54]. A reasonable strategy, therefore, is to perform CNS prophylaxis in those with a CNS-IPI score of 4 to 6. When CNS prophylaxis is used, intrathecal methotrexate or high-dose systemic methotrexate is most frequently given, with high-dose systemic methotrexate favored over intrathecal chemotherapy given that high-dose methotrexate penetrates the brain and spinal cord parenchyma, in addition to treating the cerebrospinal fluid (CSF) [55]. In contrast, intrathecal therapy only treats the CSF and requires repeated lumbar punctures or placement of an Ommaya reservoir. For DLBCL patients who present with active CSF involvement (known as lymphomatous meningitis), intrathecal chemotherapy treatments are typically given 2 or 3 times weekly until the CSF clears, followed by weekly intrathecal treatment for 4 weeks, and then monthly intrathecal treatment for 4 months [56]. For those with concurrent systemic and brain parenchymal DLBCL, a strategy of alternating R-CHOP with mid-cycle high-dose methotrexate can be successful. In addition, consolidation with high-dose therapy and auto-HCT improved survival in such patients in 1 retrospective series [57].

Relapsed/Refractory Disease. Between 30% and 40% of patients with advanced stage DLBCL will either fail to attain a remission with primary therapy (referred to as primary induction failure) or will relapse. In general, for those with progressive or relapsed disease, an updated tissue biopsy is recommended. This is especially true for patients who have had prior complete remission and have new lymph node enlargement, or those who have emergence of new sites of disease at the completion of first-line therapy.

Patients with relapsed disease are treated with systemic second-line platinum-based chemoimmunotherapy, with the usual goal of ultimately proceeding to auto-HCT. A number of platinum-based regimens have been used in this setting such as R-ICE, R-DHAP, R-GDP, R-Gem-Ox, and R-ESHAP. None of these regimens has been shown to be superior in terms of efficacy, and the choice of regimen is typically made based on the anticipated tolerance of the patient in light of comorbidities, laboratory studies, and physician preference. In the CORAL study, R-DHAP (rituximab, dexamethasone, high-dose cytarabine, cisplatin) seemed to show superior PFS in patients with the GCB subtype [58]. However, this was an unplanned subgroup analysis and R-DHAP was associated with higher renal toxicity.

Several studies have demonstrated that long-term PFS can be observed for relapsed/refractory DLBCL patients who respond to second-line therapy and then undergo high-dose therapy with auto-HCT. The Parma trial remains the only published prospective randomized trial performed in relapsed DLBCL comparing a transplant strategy to a non-transplant strategy. This study, performed in the pre-rituximab era, clearly showed a benefit in terms of DFS and OS in favor of auto-HCT versus salvage therapy alone [59]. The benefit of auto-HCT in patients treated in the rituximab era, even in patients who experience early failure (within 1 year of diagnosis), was confirmed in a retrospective analysis by the Center for International Blood and Marrow Transplant Research. In this study, a 44% 3-year PFS was seen in the early failure cohort versus 52% in the late failure cohort [60].

Some DLBCL patients are very unlikely to benefit from auto-HCT. The REFINE study focused on patients with primary induction failure or early relapse within 6 months of completing first-line therapy. Among such patients, primary progressive disease (defined as progression while still receiving first-line therapy), a high NCCN-IPI score at relapse, and MYC rearrangement were risk factors for poor PFS following auto-HCT [61]. Patients with 2 or 3 high-risk features had a 2-year OS of 10.7% compared to 74.3% for those without any high-risk features.

Allogeneic HCT (allo-HCT) is a treatment option for relapsed/refractory DLBCL. This option is more commonly considered for patients in whom an autotransplant has failed to achieve durable remission. For properly selected patients in this setting, a long-term PFS in the 30% to 40% range can be attained [62]. However, in practice, only about 20% of patients who fail auto-HCT end up undergoing allo-HCT due to rapid progression of disease, age, poor performance status, or lack of suitable donor. It has been proposed that in the coming years, allo-HCT will be utilized less commonly in this setting due to the advent of chimeric antigen receptor T-cell (CAR T) therapy.

CAR T-cell therapy genetically modifies the patient’s own T lymphocytes with a gene that encodes an antigen receptor to direct the T cells against lymphoma cells. Typically, the T cells are genetically modified and expanded in a production facility and then infused back into the patient. Axicabtagene ciloleucel is directed against the CD-19 receptor and has been approved by the US Food and Drug Administration (FDA) for treatment of patients with DLBCL who have failed 2 or more lines of systemic therapy. Use of CAR-T therapy in such patients was examined in a multicenter trial (ZUMA-1), which reported a 54% complete response rate and 52% OS rate at 18 months.63 CAR-T therapy is associated with serious side effects such as cytokine release syndrome, neurological toxicities, and prolonged cytopenias. While there are now some patients with ongoing remission 2 or more years after undergoing CAR-T therapy, it remains uncertain what proportion of patients have been truly cured with this modality. Nevertheless, this new treatment option remains a source of optimism for relapsed and refractory DLBCL patients.

Primary Mediastinal Large B-Cell Lymphoma

Primary mediastinal large B-cell lymphoma (PMBCL) is a form of DLBCL arising in the mediastinum from the thymic B cell. It is an uncommon entity and has clinical and pathologic features distinct from systemic DLBCL [64]. PMBCL accounts for 2% of all NHLs and about 7% of all DLBCL [20]. It typically affects women in the third to fourth decade of life.

Presentation and Prognostic Features

PMBCL usually presents as a locally invasive anterior mediastinal mass, often with a superior vena cava syndrome which may or may not be clinically obvious [64]. Other presentations include pericardial tamponade, thrombosis of neck veins, and acute airway obstruction. About 80% of patients present with bulky (> 10 cm) stage I or II disease [65], with distant spread uncommon on presentation. Morphologically and on GEP, PMBL has a profile more similar to classical Hodgkin lymphoma (cHL) than non-mediastinal DLBCL [66]. PMBL is distinguished from cHL by immunophenotyping: unlike cHL, PMBCL has pan B cell markers, rarely expresses CD15, and has weak CD30.

Poor prognostic features in PMBCL are Eastern Cooperative Oncology Group (ECOG) performance status greater than 2, pericardial effusion, bulky disease, and elevated serum LDH. The diagnosis of PMBCL can be difficult because the tumor is often encased with extensive fibrosis and necrosis. As a result, a needle biopsy may not yield sufficient tissue, thus making a surgical biopsy often the only viable way to obtain sufficient tissue.

Treatment

Early series suggested that PMBCL is unusually aggressive, with a poor prognosis [67]. This led to studies using more aggressive chemotherapy regimens (often in combination with mediastinal radiation) as well as upfront auto-HCT [68–70]. The addition of rituximab to treatment regimens significantly improved outcomes in PMBCL. For example, a subgroup analysis of the PMBCL patients in the MinT trial revealed a 3-year event-free survival (EFS) of 78% [71] when rituximab was combined with CHOP. Because of previous reports demonstrating radiosensitivity of PMBL, radiation was traditionally sequenced into treatment regimens for PMBL. However, this is associated with higher long-term toxicities, often a concern in PMBCL patients given that the disease frequently affects younger females, and given that breast tissue will be in the radiation field. For patients with a strong personal or family history of breast cancer or cardiovascular disease, these concerns are even more significant. More recently, the DA-EPOCH-R regimen has been shown to produce very high rates (80%–90%) of long-term DFS, without the need for mediastinal radiation in most cases [72,73]. For patients receiving R-CHOP, consolidation with mediastinal radiation is still commonly given. This approach also leads to high rates of long-term remission and, although utilizing mediastinal radiation, allows for less intensive chemotherapy. Determining which approach is most appropriate for an individual patient requires an assessment of the risks of each treatment option for that patient. A randomized trial by the International Extranodal Lymphoma Study Group (IELSG37) is evaluating whether RT may be safely omitted in PMBCL patients who achieve a complete metabolic response after R-CHOP.

Most relapses of PMBCL occur within the first 1 to 2 years and often present with extranodal disease in various organs. For those with relapsed or refractory disease, high-dose chemotherapy followed by auto-HCT provides 5-year survival rates of 50% to 80% [74–76] In a phase 1b trial evaluating the role of pembrolizumab in relapsed/refractory patients (KEYNOTE-13), 7 of 17 PMBCL patients achieved responses, with an additional 6 demonstrating stable disease [77]. This provides an additional option for patients who might be too weak to undergo auto-HCT or for those who relapse following auto-HCT.

Mantle Cell Lymphoma

The name mantle cell lymphoma (MCL) is based on the presumed normal cell counterpart to MCL, which is believed to be found in the mantle zone surrounding germinal center follicles. It represents approximately 6% of all NHL cases in the United States and Europe [78] MCL occurs at a median age of 63 to 68 years and has a male predominance.

Presentation and Prognostic Features

Patients can present with a broad spectrum of clinical features, and most patients (70%) present with advanced disease [79]. Up to one third of patients have B symptoms, with most demonstrating lymphadenopathy and bone marrow involvement. Approximately 25% present with extranodal disease as the primary presentation (eg, GI tract, pleura, breast, or orbits). MCL can involve any part of the GI tract and often presents as polypoid lesions.

Histologically, the pattern of MCL may be diffuse, nodular, mantle zone, or a combination of the these; morphologically, MCL can range from small, more irregular lymphocytes to lymphoblast-like cells. Blastoid and pleomorphic variants of MCL have a higher proliferation index and a more aggressive clinical course than other variants. MCL is characterized by the expression of pan B cell antigens (CD19+, CD20+) with coexpression of the T-cell antigen CD5, lack of CD23 expression, and nuclear expression of cyclin D1. Nuclear staining for cyclin D1 is present in more than 98% of cases [80]. In rare cases, CD5 or cyclin D1 may be negative [80]. Most MCL cases have a unique translocation that fuses the immunoglobulin heavy chain gene promoter (14q32) to the promoter of the BCL-1 gene (11q13), which encodes the cyclin D1 protein. This translocation is not unique to MCL and can be present in multiple myeloma as well. Interestingly, cyclin D1 is overproduced in cases lacking t(11:14), likely from other point mutations resulting in its overexpression [81]. Cyclin D1–negative tumors overexpress cyclin D2 or D3, with no apparent difference in clinical behavior or outcome [82]. In cyclin D1–negative cases, SOX11 expression may help with diagnosis [83]. A proliferation rate greater than 30% (as measured by Ki-67 staining), low SOX11 expression, and presence of p53 mutations have all been associated with adverse outcome.

In a minority of cases, MCL follows an indolent clinical course. For the remainder, however, MCL is an aggressive disease that generally requires treatment soon after diagnosis. When initially described in the 1980s and 1990s, treatment of MCL was characterized by low complete response rates, short durations of remission, repeated recurrences, and a median survival in the 2- to 5-year range [84]. In recent years, intensive regimens incorporating rituximab and high-dose cytarabine with or without auto-HCT have been developed and are associated with high complete response rates and median duration of first remission in the 6- to 9-year range [85–87]. Several prognostic indices have been applied to patients with MCL, including the IPI, the Follicular Lymphoma International Prognostic Index , and the Mantle Cell Lymphoma International Prognostic Index (MIPI). The MIPI was originally described based on a cohort from the period 1996 to 2004 [88], and subsequently confirmed in a separate cohort of 958 patients with MCL treated on prospective trials between 2004 and 2010 [89]. The MIPI score can identify 3 risk groups with significant survival differences (83%, 63%, and 34% survival at 5 years). A refined version of the MIPI score, the combined MIPI or MIPI-c, incorporates proliferation rate and is better able to stratify patients [90]. The blastoid variant of MCL follows a more aggressive clinical course and is associated with a high proliferation rate, shorter remissions, and a higher rate of CNS involvement [91].

In most patients, MCL is an aggressive disease with a short OS without treatment. A subset of patients may have a more indolent course [92], but unfortunately reliable factors that identify this group at the time of diagnosis are not available. Pretreatment evaluation is as with other lymphomas, with lumbar puncture and MRI of the brain also recommended for patients with the blastoid variant. For those presenting with GI symptoms, endoscopy is recommended as part of the initial evaluation as well.

Treatment

First-line Therapy. For patients under age 65 to 70 years with a good performance status and few comorbidities, an intensive induction regimen (such as R-CHOP/R-DHAP, Maxi-R-CHOP/R-araC, or R-DHAP) followed by consolidation with auto-HCT is commonly given, with a goal of achieving a durable (6–9 year) first remission [87,93,94]. Auto-HCT is now routinely followed by 3 years of maintenance rituximab based on the survival benefit seen in the recent LYSA trial [93]. At many centers, auto-HCT in first remission is a standard of care, with the greatest benefit seen in patients who have achieved a complete remission with no more than 2 lines of chemotherapy [95]. However, there remains some controversy about whether all patients truly benefit from auto-HCT in first remission, and current research efforts are focused on identifying patients most likely to benefit from auto-HCT and incorporation of new agents into first-line regimens. For patients who are not candidates for auto-HCT, bendamustine plus rituximab (BR) or R-CHOP alone or followed by maintenance rituximab is a reasonable approach [96]. Based on the StiL and BRIGHT trials, BR seems to have less toxicity and higher rates of response with no difference in OS when compared to R-CHOP [97,98].

In summary, dose-intense induction chemotherapy with consolidative auto-HCT results in high rates of long-term remission and can be considered in MCL patients who lack significant comorbidities and who understand the risks and benefits of this approach. For other patients, the less aggressive frontline approaches are more appropriate.

Relapsed/Refractory Disease

Despite initial high response rates, most patients with MCL will eventually relapse. For example, most patients given CHOP or R-CHOP alone as first-line therapy will relapse within 2 years [99]. In recent years, a number of therapies have emerged for relapsed/refractory MCL; however, the optimal sequencing of these is unclear. FDA-approved options for relapsed/refractory MCL include the proteasome inhibitor bortezomib [100,101], the BTK inhibitors ibrutinib [102,103] and acalabrutinib [104], and the immunomodulatory agent lenalidomide [105].

Auto-HCT can be considered for patients who did not undergo auto-HCT as part of first-line therapy and who had a reasonably long first remission [95]. Allo-HCT has curative potential in MCL with good evidence of a graft-versus-lymphoma effect. With a matched related or matched unrelated donor, the chance for treatment-related mortality is 15% to 25% at 1 to 2 years, with a 50% to 60% chance for long-term PFS. However, given the risk of treatment-related mortality and graft-versus-host disease, this option is typically reserved for patients with early relapse after auto-HCT, multiple relapses, or relatively chemotherapy-unresponsive disease [95,106]. A number of clinical trials for relapsed/refractory MCL are ongoing, and participation in these is encouraged whenever possible.

Burkitt Lymphoma

Burkitt lymphoma is a rare, aggressive and highly curable subtype of NHL. It can occur at any age, although peak incidence is in the first decade of life. There are 3 distinct clinical forms of Burkitt lymphoma [107]. The endemic form is common in African children and commonly involves the jaw and kidneys. The sporadic (nonendemic) form accounts for 1% to 2% of all lymphomas in the United States and Western Europe and usually has an abdominal presentation. The immunodeficiency-associated form is commonly seen in HIV patients with a relatively preserved CD4 cell count.

Patients typically present with rapidly growing masses and tumor lysis syndrome. CNS and bone marrow involvement are common. Burkitt lymphoma cells are high-grade, rapidly proliferating medium-sized cells with a monomorphic appearance. Biopsies show a classic histological appearance known as a “starry sky pattern” due to benign macrophages engulfing debris resulting from apoptosis. It is derived from a germinal center B cell and has distinct oncogenic pathways. Translocations such as t(8;14), t(2;8) or t(8;22) juxtapose the MYC locus with immunoglobulin heavy or light chain loci and result in MYC overexpression. Burkitt lymphoma is typically CD10-positive and BCL-2-negative, with a MYC translocation and a proliferation rate greater than 95%.

With conventional NHL regimens, Burkitt lymphoma had a poor prognosis, with complete remission in the 30% to 70% range and low rates of long-term remission. With the introduction of short-term, dose-intensive, multiagent chemotherapy regimens (adapted from pediatric acute lymphoblastic leukemia [ALL] regimens), the complete remission rate improved to 60% to 90% [107]. Early stage disease (localized or completely resected intra-abdominal disease) can have complete remission rates of 100%, with 2- to 5-year freedom-from-progression rates of 95%. CNS prophylaxis, including high-dose methotrexate, high-dose cytarabine, and intrathecal chemotherapy, is a standard component of Burkitt lymphoma regimens (CNS relapse rates can reach 50% without prophylactic therapy). Crucially, relapse after 1 to 2 years is very rare following complete response to induction therapy. Classically, several intensive regimens have been used for Burkitt lymphoma. In recent years, the most commonly used regimens have been the modified Magrath regimen of R-CODOX-M/IVAC and R-hyperCVAD. DA-EPOCH-R has also been used, typically for older, more frail, or HIV-positive patients. However, at the American Society of Hematology 2017 annual meeting, results from the NCI 9177 trial were presented which validated, in a prospective multi-center fashion, the use of DA-EPOCH-R in all Burkitt lymphoma patients [108]. In NCI 9177, low-risk patients (defined as normal LDH, ECOG performance score 0 or 1, ≤ stage II, and no tumor lesion > 7 cm) received 2 cycles of DA-EPOCH-R without intrathecal therapy followed by PET. If interim PET was negative, low-risk patients then received 1 more cycle of DA-EPOCH-R. High-risk patients with negative brain MRI and CSF cytology/flow cytometry received 2 cycles of DA-EPOCH-R with intrathecal therapy (2 doses per cycle) followed by PET. Unless interim PET showed progression, high-risk patients received 4 additional cycles of DA-EPOCH-R including methotrexate 12 mg intrathecally on days 1 and 5 (8 total doses). With a median follow-up of 36 months, this regimen resulted in an EFS of 85.7%. As expected, patients with CNS, marrow, or peripheral blood involvement fared worse. For those without CNS, marrow, or peripheral blood involvement, the results were excellent, with an EFS of 94.6% compared to 62.8% for those with CNS, bone marrow, or blood involvement at diagnosis.

Although no standard of care has been defined, patients with relapsed/refractory Burkitt lymphoma are often given standard second-line aggressive NHL regimens (eg, R-ICE); for those with chemosensitive disease, auto- or allo-HCT is often pursued, with long-term remissions possible following HCT [109].

Lymphoblastic Lymphoma

Lymphoblastic lymphoma (LBL) is a rare disease postulated to arise from precursor B or T lymphoblasts at varying stages of differentiation. Accounting for approximately 2% of all NHLs, 85% to 90% of all cases have a T-cell phenotype, while B-cell LBL comprises approximately 10% to 15% of cases. LBL and ALL are thought to represent the same disease entity, but LBL has been arbitrarily defined as cases with lymph node or mediastinal disease. Those with significant (> 25%) bone marrow or peripheral blood involvement are classified as ALL.

Precursor T-cell LBL patients are usually adolescent and young males who commonly present with a mediastinal mass and peripheral lymphadenopathy. Precursor B-cell LBL patients are usually older (median age 39 years) with peripheral lymphadenopathy and extranodal involvement. Mediastinal involvement with B-cell LBL is uncommon, and there is no male predominance. LBL has a propensity for dissemination to the bone marrow and CNS.

Morphologically, the tumor cells are medium sized, with a scant cytoplasm and finely dispersed chromatin. Mitotic features and apoptotic bodies are present since it is a high-grade malignancy. The lymphoblasts are typically positive for CD7 and either surface or cytoplasmic CD3. Terminal deoxynucleotidyl transferase expression is a defining feature. Other markers such as CD19, CD22, CD20, CD79a, CD45, and CD10 are variably expressed. Poor prognostic factors in T-cell LBL are female gender, age greater than 35 years, complex cytogenetics, and lack of a matched sibling donor.

Regimens for LBL are based on dose-dense, multi-agent protocols used in ALL. Most of these regimens are characterized by intensive remission-induction chemotherapy, CNS prophylaxis, a phase of consolidation therapy, and a prolonged maintenance phase, often lasting for 12 to 18 months with long-term DFS rates of 40% to 70% [110,111]. High-dose therapy with auto-HCT or allo-HCT in first complete response has been evaluated in an attempt to reduce the incidence of relapse [112]. However, the intensity of primary chemotherapy appears to be a stronger determinant of long-term survival than the use of HCT as consolidation. As a result, HCT is not routinely applied to patients in first complete remission following modern induction regimens. After relapse, prognosis is poor, with median survival rates of 6 to 9 months with conventional chemotherapy, although long-term survival rates of 30% and 20%, respectively, are reported after HCT in relapsed and primary refractory disease [113].

Treatment options in relapsed disease are limited. Nelarabine can produce responses in up to 40% of relapsed/refractory LBL/ALL patients [114]. For the minority of LBL patients with a B-cell phenotype, emerging options for relapsed/refractory LBL/ALL such as inotuzumab, blinatumomab, or anti-CD19 CAR T-cell therapy should be considered. These are not options for the majority who have a T-cell phenotype, and treatment options for these patients are limited to conventional relapsed/refractory ALL and aggressive NHL regimens.

Summary

Aggressive NHLs are characterized by rapid clinical progression without therapy. However, a significant proportion of patients are cured with appropriate combination chemotherapy or combined modality (chemotherapy + RT) regimens. In contrast, the indolent lymphomas have a relatively good prognosis (median survival of 10 years or longer) but usually are not curable in advanced clinical stages. Overall 5-year survival for aggressive NHLs with current treatment is approximately 50% to 60%, with relapses typically occurring within the first 5 years. Treatment strategies for relapsed patients offer some potential for cure; however, clinical trial participation should be encouraged whenever possible to investigate new approaches for improving outcomes in this patient population.

Corresponding author: Timothy S. Fenske, MD, Division of Hematology & Oncology, Medical College of Wisconsin, 9200 W. Wisconsin Ave., Milwaukee, WI 53226.

Abstract

• Objective: To review the diagnosis and management of aggressive B-cell non-Hodgkin lymphoma (NHL).
• Methods: Review of the literature.
• Results: NHL comprises a wide variety of malignant hematologic disorders with varying clinical and biological features. Aggressive NHLs are characterized by rapid clinical progression without therapy. However, a significant proportion of patients are cured with appropriate combination chemotherapy or combined modality regimens. In contrast, the indolent lymphomas have a relatively good prognosis (median survival of 10 years or longer) but usually are not curable in advanced clinical stages. Overall 5-year survival for aggressive NHLs with current treatment is approximately 50% to 60%, with relapses typically occurring within the first 5 years.
• Conclusion: Treatment strategies for relapsed patients offer some potential for cure; however, clinical trial participation should be encouraged whenever possible to investigate new approaches for improving outcomes in this patient population.

Non-Hodgkin lymphoma (NHL) comprises a wide variety of malignant hematologic disorders with varying clinical and biological features. The more than 60 separate NHL subtypes can be classified according to cell of origin (B cell versus T cell), anatomical location (eg, orbital, testicular, bone, central nervous system), clinical behavior (indolent versus aggressive), histological features, or cytogenetic abnormalities. Although various NHL classification schemes have been used over the years, the World Health Organization (WHO) classification is now widely accepted as the definitive pathologic classification system for lymphoproliferative disorders, incorporating morphologic, immunohistochemical, flow cytometric, cytogenetic, and molecular features [1]. While the pathologic and molecular subclassification of NHL has become increasingly refined in recent years, from a management standpoint, classification based on clinical behavior remains very useful. This approach separates NHL subtypes into indolent versus aggressive categories. Whereas indolent NHLs may remain clinically insignificant for months to years, aggressive B-cell NHLs generally become life-threatening within weeks to months without treatment.

Epidemiology

Data from cancer registries show a steady, unexplainable increase in the incidence of NHL during the second half of the 20th century; the incidence has subsequently plateaued. There was a significant increase in NHL incidence between 1970 and 1995, which has been attributed in part to the HIV epidemic. More than 72,000 new cases of NHL were diagnosed in the United States in 2017, compared to just over 8000 cases of Hodgkin lymphoma, making NHL the sixth most common cancer in adult men and the fifth most common in adult women [2]. NHL appears to occur more frequently in Western countries than in Asian populations.

Various factors associated with increased risk for B-cell NHL have been identified over the years, including occupational and environmental exposure to certain pesticides and herbicides [3], immunosuppression associated with HIV infection [4], autoimmune disorders [5], iatrogenically induced immune suppression in the post-transplant and other settings [6], family history of NHL [7], and a personal history of a prior cancer, including Hodgkin lymphoma and prior NHL [8]. In terms of infectious agents associated with aggressive B-cell NHLs, Epstein-Barr virus (EBV) has a clear pathogenic role in Burkitt lymphoma, in many cases of post-transplant lymphoproliferative disorders, and in some cases of HIV-related aggressive B-cell lymphoma [9]. Human herpesvirus-8 viral genomes have been found in virtually all cases of primary effusion lymphomas [10]. Epidemiological studies also have linked hepatitis B and C to increased incidences of certain NHL subtypes [11–13], including primary hepatic diffuse large B-cell lymphoma (DLBCL). Similarly, Helicobacter pylori has been associated with gastric DLBCL.

Staging and Workup

A tissue biopsy is essential in the diagnosis and management of NHL. The most significant disadvantage of fine-needle aspiration cytology is the lack of histologic architecture. The optimal specimen is an excisional biopsy; when this cannot be performed, a core needle biopsy, ideally using a 16-gauge or larger caliber needle, is the next best choice.

The baseline tests appropriate for most cases of newly diagnosed aggressive B-cell NHL are listed in Table 1. 

Prior to the initiation of treatment, patients should always undergo a thorough cardiac and pulmonary evaluation, especially if the patient will be treated with an anthracycline or mediastinal irradiation. Central nervous system (CNS) evaluation with magnetic resonance imaging (MRI) and lumbar puncture is essential if there are neurological signs or symptoms. In addition, certain anatomical sites including the testicles, paranasal sinuses, kidney, adrenal glands, and epidural space have been associated with increased involvement of the CNS and may warrant MRI evaluation and lumbar puncture. Certain NHL subtypes like Burkitt lymphoma, high-grade NHL with translocations of MYC and BCL-2 or BCL-6 (double-hit lymphoma), blastoid mantle cell lymphoma, and lymphoblastic lymphoma have a high risk of CNS involvement, and patients with these subtypes need CNS evaluation.

The Lugano classification is used to stage patients with NHL [14]. This classification is based on the Ann Arbor staging system and uses the distribution and number of tumor sites to stage disease. In general, this staging system in isolation is of limited value in predicting survival after treatment. However, the Ann Arbor stage does have prognostic impact when incorporated into risk scoring systems such as the International Prognostic Index (IPI). In clinical practice, the Ann Arbor stage is useful primarily to determine eligibility for localized therapy approaches. The absence or presence of systemic symptoms such as fevers, drenching night sweats, or weight loss (> 10% of baseline over 6 months or less) is designated by A or B, respectively.

Diffuse Large B-Cell Lymphoma

DLBCL is the most common lymphoid neoplasm in adults, accounting for about 25% of all NHL cases [2]. It is increasingly clear that the diagnostic category of DLBCL is quite heterogeneous in terms of morphology, genetics, and biologic behavior. A number of clinicopathologic subtypes of DLBCL exist, such as T cell/histiocyte–rich large B-cell lymphoma, primary mediastinal large B-cell lymphoma, intravascular large B-cell lymphoma, DLBCL associated with chronic inflammation, lymphomatoid granulomatosis, and EBV-positive large B-cell lymphoma, among others. Gene expression profiling (GEP) can distinguish 2 cell of origin DLBCL subtypes: the germinal center B-cell (GCB) and activated B-cell (ABC) subtypes [15].

DLBCL may be primary (de novo) or may arise through the transformation of many different types of low-grade B-cell lymphomas. This latter scenario is referred to as histologic transformation or transformed lymphoma. In some cases, patients may have a previously diagnosed low-grade B-cell NHL; in other cases, both low-grade and aggressive B-cell NHL may be diagnosed concurrently. The presence of elements of both low-grade and aggressive B-cell NHL in the same biopsy specimen is sometimes referred to as a composite lymphoma.

In the United States, incidence varies by ethnicity, with DLBCL being more common in Caucasians than other races [16]. There is a slight male predominance (55%), median age at diagnosis is 65 years [16,17] and the incidence increases with age.

Presentation, Pathology, and Prognostic Factors

The most common presentation of patients with DLBCL is rapidly enlarging lymphadenopathy, usually in the neck or abdomen. Extranodal/extramedullary presentation is seen in approximately 40% of cases, with the gastrointestinal (GI) tract being the most common site. However, extranodal DLBCL can arise in virtually any tissue [18]. Nodal DLBCL presents with symptoms related to the sites of involvement (eg, shortness of breath or chest pain with mediastinal lymphadenopathy), while extranodal DLBCL typically presents with symptoms secondary to dysfunction at the site of origin. Up to one third of patients present with constitutional symptoms (B symptoms) and more than 50% have elevated serum lactate dehydrogenase (LDH) at diagnosis [19].

Approximately 40% of patients present with stage I/II disease. Of these, only a subset present with stage I, or truly localized disease (defined as that which can be contained within 1 irradiation field). About 60% of patients present with advanced (stage III–IV) disease [20]. The bone marrow is involved in about 15% to 30% of cases. DLBCL involvement of the bone marrow is associated with a less favorable prognosis. Patients with DLBCL elsewhere may have low-grade NHL involvement of the bone marrow. Referred to as discordant bone marrow involvement [21], this feature does not carry the same poor prognosis associated with transformed disease [22] or DLBCL involvement of the bone marrow [23].

DLBCL is defined as a neoplasm of large B-lymphoid cells with a diffuse growth pattern. The proliferative fraction of cells, as determined by Ki-67 staining, is usually greater than 40%, and may even exceed 90%. Lymph nodes usually demonstrate complete effacement of the normal architecture by sheets of atypical lymphoid cells. Tumor cells in DLBCL generally express pan B-cell antigens (CD19, CD20, CD22, CD79a, Pax-5) as well as CD45 and surface immunoglobulin. Between 20% and 37% of DLBCL cases express the BCL-2 protein [24], and about 70% express the BCL-6 protein [25]. C-MYC protein expression is seen in a higher percentage (~ 30%–50%) of cases of DLBCL [26].

Many factors are associated with outcome in DLBCL. The IPI score was developed in the pre-rituximab era and is a robust prognostic tool. This simple tool uses 5 easily obtained clinical factors (age > 60 years, impaired performance status, elevated LDH, > 1 extranodal site of disease, and stage III/IV disease). By summing these factors, 4 groups with distinct 5-year overall survival (OS) rates ranging from 26% to 73% were identified (Table 2). 

Cytogenetic and molecular factors also predict outcome in DLBCL. The ABC subtype distinguished by GEP has consistently been shown to have inferior outcomes with first-line therapy. As GEP is not routinely available in clinical practice, immunohistochemical (IHC) approaches (eg, the Hans algorithm) have been developed that can approximate the GEP subtypes. These IHC approaches have approximately 80% concordance with GEP [28]. The 3 most common chromosomal translocations in DLBCL involve BCL-2, BCL-6 and MYC. MYC-rearranged DLBCLs have a less favorable prognosis [29,30]. Cases in which a MYC translocation occurs in combination with a BCL-2 or BCL-6 translocation are commonly referred to as double-hit lymphoma (DHL); cases with all 3 translocations are referred to as triple-hit lymphoma (THL). Both DHL and THL have a worse prognosis with standard DLBCL therapy compared to non-DHL/THL cases. In the 2016 revised WHO classification, DHL and THL are an entity technically distinct from DLBCL, referred to as high-grade B-cell lymphoma [1]. In some cases, MYC and BCL-2 protein overexpression occurs in the absence of chromosomal translocations. Cases in which MYC and BCL-2 are overexpressed (by IHC) are referred to as double expressor lymphoma (DEL), and also have inferior outcome compared with non-DEL DLBCL [31,32]. Interestingly, MYC protein expression alone does not confer inferior outcomes, unlike isolated MYC translocation, which is associated with inferior outcomes.

Treatment

First-Line Therapy. DLBCL is an aggressive disease and, in most cases, survival without treatment can be measured in weeks to months. The advent of combination chemotherapy (CHOP [cyclophosphamide, doxorubicin, vincristine, and prednisone] or CHOP-like regimens) led to disease-free survival (DFS) rates of 35% to 40% at 3 to 5 years [33]. The addition of rituximab to CHOP (R-CHOP) has improved both progression-free surivial (PFS) and OS [34,35].

Treatment options vary for patients with localized (stage I/II) and advanced (stage III/IV) disease. Options for limited-stage DLBCL include an abbreviated course of R-CHOP (3 or 4 cycles) with involved-field radiation therapy (IFRT) versus a full course (6–8 cycles) of R-CHOP without radiation therapy (RT). Most studies comparing combined modality therapy (chemotherapy plus RT) versus chemotherapy alone were conducted in the pre-rituximab era. With the introduction of rituximab, Persky and colleagues [36] studied the use of 3 cycles of R-CHOP followed by RT, demonstrating a slightly improved OS of 92% at 4 years as compared to 88% in a historical cohort. The French LYSA/GOELAMS group performed the only direct comparison in the rituximab era (4 cycles of R-CHOP followed by RT versus 4 cycles of R-CHOP followed by 2 additional cycles of R-CHOP) and reported similar outcomes between both arms [37], with OS of 92% in the R-CHOP alone arm and 96% in the R-CHOP + RT arm (nonsignificant difference statistically). IFRT alone is not recommended other than for palliation in patients who cannot tolerate chemotherapy or combined modality therapy. Stage I and II patients with bulky disease (> 10 cm) have a prognosis similar to patients with advanced DLBCL and should be treated aggressively with 6 to 8 cycles of R-CHOP with or without RT [36].

For patients with advanced stage disease, a full course of R-CHOP-21 (6–8 cycles given on a 21-day cycle) is the standard of care. This approach results in OS rates of 70% and 60% at 2 and 5 years, respectively. For older adults unable to tolerate full-dose R-CHOP, attenuated versions of R-CHOP with decreased dose density or decreased dose intensity have been developed [38]. Numerous randomized trials have attempted to improve upon the results of R-CHOP-21 using strategies such as infusional chemotherapy (DA-EPOCH-R [etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, rituximab]) [39]; dose-dense therapy (R-CHOP-14); replacement of rituximab with obinutuzuimab [40]; addition of novel agents such as bortezomib [41], lenalidomide[42], or ibrutinib [43,44] to R-CHOP; and various maintenance strategies such as rituximab, lenalidomide [45], enzastaurin [46], and everolimus [47]. Unfortunately, none of these strategies has been shown to improve OS in DLBCL. In part this appears to be due to the fact that inclusion/exclusion criteria for DLBCL trials have been too strict, such that the most severely ill DLBCL patients are typically not included. As a result, the results in the control arms have ended up better than what was expected based on historical data. Efforts are underway to include all patients in future first-line DLBCL studies.

Currently, autologous hematopoietic cell transplantation (auto-HCT) is not routinely used in the initial treatment of DLBCL. In the pre-rituximab era, numerous trials were conducted in DLBCL patients with high and/or high-intermediate risk disease based on the IPI score to determine if outcomes could be improved with high-dose therapy and auto-HCT as consolidation after patients achieved complete remission with first-line therapy. The results of these trials were conflicting. A 2003 meta-analysis of 11 such trials concluded that the results were very heterogeneous and showed no OS benefit [48]. More recently, the Southwestern Oncology Group published the results of a prospective trial testing the impact of auto-HCT for consolidation of aggressive NHL patients with an IPI score of 3 to 5 who achieved complete remission with first-line therapy with CHOP or R-CHOP. In this study, 75% of the patients had DLBCL and, of the B-cell NHL patients, 47% received R-CHOP. A survival benefit was seen only in the subgroup that had an IPI score of 4 or 5; a subgroup analysis restricted to those receiving R-CHOP as induction was not performed, however [49]. As a result, this area remains controversial, with most institutions not routinely performing auto-HCT for any DLBCL patients in first complete remission and some institutions considering auto-HCT in first complete remission for patients with an IPI score of 4 or 5. These studies all used the IPI score to identify high-risk patients. It is possible that the use of newer biomarkers or minimal-residual disease analysis will lead to a more robust algorithm for identifying high-risk patients and selecting patients who might benefit from consolidation of first complete remission with auto-HCT.

For patients with DHL or THL, long-term PFS with standard R-CHOP therapy is poor (20% to 40%) [50,51]. Treatment with more intensive first-line regimens such as DA-EPOCH-R, R-hyperCVAD (rituximab plus hyperfractionated cyclophosphamide, vincristine, doxorubicin, dexamethasone), or CODOX-M/IVAC±R (cyclophosphamide, vincristine, doxorubicin, high‐dose methotrexate/ifosfamide, etoposide, high‐dose cytarabine ± rituximab), along with CNS prophylaxis, however, has been shown to produce superior outcomes [52], with 3-year relapse-free survival rates of 88% compared to 56% for R-CHOP. For patients who achieve a complete response by PET/CT scan after intensive induction, consolidation with auto-HCT has not been shown to improve outcomes based on retrospective analysis. However for DHL/THL patients who achieve complete response after R-CHOP, PFS was improved if auto-HCT was given as consolidation of first remission [53].

Patients with DLBCL have an approximately 5% risk of subsequently developing CNS involvement. Historically (in the pre-rituximab era), patients who presented with multiple sites of extranodal disease and/or extensive bone marrow involvement and/or an elevated LDH had an increased risk (up to 20%–30%) of developing CNS involvement. In addition, patients with involvement of certain anatomical sites (testicular, paranasal sinuses, epidural space) had an increased risk of CNS disease. Several algorithms have been proposed to identify patients who should receive prophylactic CNS therapy. One of the most robust tools for this purpose is the CNS-IPI, which is a 6-point score consisting of the 5 IPI elements, plus 1 additional point if the adrenal glands or kidneys are involved. Importantly, the CNS-IPI was developed and validated in patients treated with R-CHOP-like therapy. Subsequent risk of CNS relapse was 0.6%, 3.4%, and 10.2% for those with low-, intermediate- and high-risk CNS-IPI scores, respectively [54]. A reasonable strategy, therefore, is to perform CNS prophylaxis in those with a CNS-IPI score of 4 to 6. When CNS prophylaxis is used, intrathecal methotrexate or high-dose systemic methotrexate is most frequently given, with high-dose systemic methotrexate favored over intrathecal chemotherapy given that high-dose methotrexate penetrates the brain and spinal cord parenchyma, in addition to treating the cerebrospinal fluid (CSF) [55]. In contrast, intrathecal therapy only treats the CSF and requires repeated lumbar punctures or placement of an Ommaya reservoir. For DLBCL patients who present with active CSF involvement (known as lymphomatous meningitis), intrathecal chemotherapy treatments are typically given 2 or 3 times weekly until the CSF clears, followed by weekly intrathecal treatment for 4 weeks, and then monthly intrathecal treatment for 4 months [56]. For those with concurrent systemic and brain parenchymal DLBCL, a strategy of alternating R-CHOP with mid-cycle high-dose methotrexate can be successful. In addition, consolidation with high-dose therapy and auto-HCT improved survival in such patients in 1 retrospective series [57].

Relapsed/Refractory Disease. Between 30% and 40% of patients with advanced stage DLBCL will either fail to attain a remission with primary therapy (referred to as primary induction failure) or will relapse. In general, for those with progressive or relapsed disease, an updated tissue biopsy is recommended. This is especially true for patients who have had prior complete remission and have new lymph node enlargement, or those who have emergence of new sites of disease at the completion of first-line therapy.

Patients with relapsed disease are treated with systemic second-line platinum-based chemoimmunotherapy, with the usual goal of ultimately proceeding to auto-HCT. A number of platinum-based regimens have been used in this setting such as R-ICE, R-DHAP, R-GDP, R-Gem-Ox, and R-ESHAP. None of these regimens has been shown to be superior in terms of efficacy, and the choice of regimen is typically made based on the anticipated tolerance of the patient in light of comorbidities, laboratory studies, and physician preference. In the CORAL study, R-DHAP (rituximab, dexamethasone, high-dose cytarabine, cisplatin) seemed to show superior PFS in patients with the GCB subtype [58]. However, this was an unplanned subgroup analysis and R-DHAP was associated with higher renal toxicity.

Several studies have demonstrated that long-term PFS can be observed for relapsed/refractory DLBCL patients who respond to second-line therapy and then undergo high-dose therapy with auto-HCT. The Parma trial remains the only published prospective randomized trial performed in relapsed DLBCL comparing a transplant strategy to a non-transplant strategy. This study, performed in the pre-rituximab era, clearly showed a benefit in terms of DFS and OS in favor of auto-HCT versus salvage therapy alone [59]. The benefit of auto-HCT in patients treated in the rituximab era, even in patients who experience early failure (within 1 year of diagnosis), was confirmed in a retrospective analysis by the Center for International Blood and Marrow Transplant Research. In this study, a 44% 3-year PFS was seen in the early failure cohort versus 52% in the late failure cohort [60].

Some DLBCL patients are very unlikely to benefit from auto-HCT. The REFINE study focused on patients with primary induction failure or early relapse within 6 months of completing first-line therapy. Among such patients, primary progressive disease (defined as progression while still receiving first-line therapy), a high NCCN-IPI score at relapse, and MYC rearrangement were risk factors for poor PFS following auto-HCT [61]. Patients with 2 or 3 high-risk features had a 2-year OS of 10.7% compared to 74.3% for those without any high-risk features.

Allogeneic HCT (allo-HCT) is a treatment option for relapsed/refractory DLBCL. This option is more commonly considered for patients in whom an autotransplant has failed to achieve durable remission. For properly selected patients in this setting, a long-term PFS in the 30% to 40% range can be attained [62]. However, in practice, only about 20% of patients who fail auto-HCT end up undergoing allo-HCT due to rapid progression of disease, age, poor performance status, or lack of suitable donor. It has been proposed that in the coming years, allo-HCT will be utilized less commonly in this setting due to the advent of chimeric antigen receptor T-cell (CAR T) therapy.

CAR T-cell therapy genetically modifies the patient’s own T lymphocytes with a gene that encodes an antigen receptor to direct the T cells against lymphoma cells. Typically, the T cells are genetically modified and expanded in a production facility and then infused back into the patient. Axicabtagene ciloleucel is directed against the CD-19 receptor and has been approved by the US Food and Drug Administration (FDA) for treatment of patients with DLBCL who have failed 2 or more lines of systemic therapy. Use of CAR-T therapy in such patients was examined in a multicenter trial (ZUMA-1), which reported a 54% complete response rate and 52% OS rate at 18 months.63 CAR-T therapy is associated with serious side effects such as cytokine release syndrome, neurological toxicities, and prolonged cytopenias. While there are now some patients with ongoing remission 2 or more years after undergoing CAR-T therapy, it remains uncertain what proportion of patients have been truly cured with this modality. Nevertheless, this new treatment option remains a source of optimism for relapsed and refractory DLBCL patients.

Primary Mediastinal Large B-Cell Lymphoma

Primary mediastinal large B-cell lymphoma (PMBCL) is a form of DLBCL arising in the mediastinum from the thymic B cell. It is an uncommon entity and has clinical and pathologic features distinct from systemic DLBCL [64]. PMBCL accounts for 2% of all NHLs and about 7% of all DLBCL [20]. It typically affects women in the third to fourth decade of life.

Presentation and Prognostic Features

PMBCL usually presents as a locally invasive anterior mediastinal mass, often with a superior vena cava syndrome which may or may not be clinically obvious [64]. Other presentations include pericardial tamponade, thrombosis of neck veins, and acute airway obstruction. About 80% of patients present with bulky (> 10 cm) stage I or II disease [65], with distant spread uncommon on presentation. Morphologically and on GEP, PMBL has a profile more similar to classical Hodgkin lymphoma (cHL) than non-mediastinal DLBCL [66]. PMBL is distinguished from cHL by immunophenotyping: unlike cHL, PMBCL has pan B cell markers, rarely expresses CD15, and has weak CD30.

Poor prognostic features in PMBCL are Eastern Cooperative Oncology Group (ECOG) performance status greater than 2, pericardial effusion, bulky disease, and elevated serum LDH. The diagnosis of PMBCL can be difficult because the tumor is often encased with extensive fibrosis and necrosis. As a result, a needle biopsy may not yield sufficient tissue, thus making a surgical biopsy often the only viable way to obtain sufficient tissue.

Treatment

Early series suggested that PMBCL is unusually aggressive, with a poor prognosis [67]. This led to studies using more aggressive chemotherapy regimens (often in combination with mediastinal radiation) as well as upfront auto-HCT [68–70]. The addition of rituximab to treatment regimens significantly improved outcomes in PMBCL. For example, a subgroup analysis of the PMBCL patients in the MinT trial revealed a 3-year event-free survival (EFS) of 78% [71] when rituximab was combined with CHOP. Because of previous reports demonstrating radiosensitivity of PMBL, radiation was traditionally sequenced into treatment regimens for PMBL. However, this is associated with higher long-term toxicities, often a concern in PMBCL patients given that the disease frequently affects younger females, and given that breast tissue will be in the radiation field. For patients with a strong personal or family history of breast cancer or cardiovascular disease, these concerns are even more significant. More recently, the DA-EPOCH-R regimen has been shown to produce very high rates (80%–90%) of long-term DFS, without the need for mediastinal radiation in most cases [72,73]. For patients receiving R-CHOP, consolidation with mediastinal radiation is still commonly given. This approach also leads to high rates of long-term remission and, although utilizing mediastinal radiation, allows for less intensive chemotherapy. Determining which approach is most appropriate for an individual patient requires an assessment of the risks of each treatment option for that patient. A randomized trial by the International Extranodal Lymphoma Study Group (IELSG37) is evaluating whether RT may be safely omitted in PMBCL patients who achieve a complete metabolic response after R-CHOP.

Most relapses of PMBCL occur within the first 1 to 2 years and often present with extranodal disease in various organs. For those with relapsed or refractory disease, high-dose chemotherapy followed by auto-HCT provides 5-year survival rates of 50% to 80% [74–76] In a phase 1b trial evaluating the role of pembrolizumab in relapsed/refractory patients (KEYNOTE-13), 7 of 17 PMBCL patients achieved responses, with an additional 6 demonstrating stable disease [77]. This provides an additional option for patients who might be too weak to undergo auto-HCT or for those who relapse following auto-HCT.

Mantle Cell Lymphoma

The name mantle cell lymphoma (MCL) is based on the presumed normal cell counterpart to MCL, which is believed to be found in the mantle zone surrounding germinal center follicles. It represents approximately 6% of all NHL cases in the United States and Europe [78] MCL occurs at a median age of 63 to 68 years and has a male predominance.

Presentation and Prognostic Features

Patients can present with a broad spectrum of clinical features, and most patients (70%) present with advanced disease [79]. Up to one third of patients have B symptoms, with most demonstrating lymphadenopathy and bone marrow involvement. Approximately 25% present with extranodal disease as the primary presentation (eg, GI tract, pleura, breast, or orbits). MCL can involve any part of the GI tract and often presents as polypoid lesions.

Histologically, the pattern of MCL may be diffuse, nodular, mantle zone, or a combination of the these; morphologically, MCL can range from small, more irregular lymphocytes to lymphoblast-like cells. Blastoid and pleomorphic variants of MCL have a higher proliferation index and a more aggressive clinical course than other variants. MCL is characterized by the expression of pan B cell antigens (CD19+, CD20+) with coexpression of the T-cell antigen CD5, lack of CD23 expression, and nuclear expression of cyclin D1. Nuclear staining for cyclin D1 is present in more than 98% of cases [80]. In rare cases, CD5 or cyclin D1 may be negative [80]. Most MCL cases have a unique translocation that fuses the immunoglobulin heavy chain gene promoter (14q32) to the promoter of the BCL-1 gene (11q13), which encodes the cyclin D1 protein. This translocation is not unique to MCL and can be present in multiple myeloma as well. Interestingly, cyclin D1 is overproduced in cases lacking t(11:14), likely from other point mutations resulting in its overexpression [81]. Cyclin D1–negative tumors overexpress cyclin D2 or D3, with no apparent difference in clinical behavior or outcome [82]. In cyclin D1–negative cases, SOX11 expression may help with diagnosis [83]. A proliferation rate greater than 30% (as measured by Ki-67 staining), low SOX11 expression, and presence of p53 mutations have all been associated with adverse outcome.

In a minority of cases, MCL follows an indolent clinical course. For the remainder, however, MCL is an aggressive disease that generally requires treatment soon after diagnosis. When initially described in the 1980s and 1990s, treatment of MCL was characterized by low complete response rates, short durations of remission, repeated recurrences, and a median survival in the 2- to 5-year range [84]. In recent years, intensive regimens incorporating rituximab and high-dose cytarabine with or without auto-HCT have been developed and are associated with high complete response rates and median duration of first remission in the 6- to 9-year range [85–87]. Several prognostic indices have been applied to patients with MCL, including the IPI, the Follicular Lymphoma International Prognostic Index , and the Mantle Cell Lymphoma International Prognostic Index (MIPI). The MIPI was originally described based on a cohort from the period 1996 to 2004 [88], and subsequently confirmed in a separate cohort of 958 patients with MCL treated on prospective trials between 2004 and 2010 [89]. The MIPI score can identify 3 risk groups with significant survival differences (83%, 63%, and 34% survival at 5 years). A refined version of the MIPI score, the combined MIPI or MIPI-c, incorporates proliferation rate and is better able to stratify patients [90]. The blastoid variant of MCL follows a more aggressive clinical course and is associated with a high proliferation rate, shorter remissions, and a higher rate of CNS involvement [91].

In most patients, MCL is an aggressive disease with a short OS without treatment. A subset of patients may have a more indolent course [92], but unfortunately reliable factors that identify this group at the time of diagnosis are not available. Pretreatment evaluation is as with other lymphomas, with lumbar puncture and MRI of the brain also recommended for patients with the blastoid variant. For those presenting with GI symptoms, endoscopy is recommended as part of the initial evaluation as well.

Treatment

First-line Therapy. For patients under age 65 to 70 years with a good performance status and few comorbidities, an intensive induction regimen (such as R-CHOP/R-DHAP, Maxi-R-CHOP/R-araC, or R-DHAP) followed by consolidation with auto-HCT is commonly given, with a goal of achieving a durable (6–9 year) first remission [87,93,94]. Auto-HCT is now routinely followed by 3 years of maintenance rituximab based on the survival benefit seen in the recent LYSA trial [93]. At many centers, auto-HCT in first remission is a standard of care, with the greatest benefit seen in patients who have achieved a complete remission with no more than 2 lines of chemotherapy [95]. However, there remains some controversy about whether all patients truly benefit from auto-HCT in first remission, and current research efforts are focused on identifying patients most likely to benefit from auto-HCT and incorporation of new agents into first-line regimens. For patients who are not candidates for auto-HCT, bendamustine plus rituximab (BR) or R-CHOP alone or followed by maintenance rituximab is a reasonable approach [96]. Based on the StiL and BRIGHT trials, BR seems to have less toxicity and higher rates of response with no difference in OS when compared to R-CHOP [97,98].

In summary, dose-intense induction chemotherapy with consolidative auto-HCT results in high rates of long-term remission and can be considered in MCL patients who lack significant comorbidities and who understand the risks and benefits of this approach. For other patients, the less aggressive frontline approaches are more appropriate.

Relapsed/Refractory Disease

Despite initial high response rates, most patients with MCL will eventually relapse. For example, most patients given CHOP or R-CHOP alone as first-line therapy will relapse within 2 years [99]. In recent years, a number of therapies have emerged for relapsed/refractory MCL; however, the optimal sequencing of these is unclear. FDA-approved options for relapsed/refractory MCL include the proteasome inhibitor bortezomib [100,101], the BTK inhibitors ibrutinib [102,103] and acalabrutinib [104], and the immunomodulatory agent lenalidomide [105].

Auto-HCT can be considered for patients who did not undergo auto-HCT as part of first-line therapy and who had a reasonably long first remission [95]. Allo-HCT has curative potential in MCL with good evidence of a graft-versus-lymphoma effect. With a matched related or matched unrelated donor, the chance for treatment-related mortality is 15% to 25% at 1 to 2 years, with a 50% to 60% chance for long-term PFS. However, given the risk of treatment-related mortality and graft-versus-host disease, this option is typically reserved for patients with early relapse after auto-HCT, multiple relapses, or relatively chemotherapy-unresponsive disease [95,106]. A number of clinical trials for relapsed/refractory MCL are ongoing, and participation in these is encouraged whenever possible.

Burkitt Lymphoma

Burkitt lymphoma is a rare, aggressive and highly curable subtype of NHL. It can occur at any age, although peak incidence is in the first decade of life. There are 3 distinct clinical forms of Burkitt lymphoma [107]. The endemic form is common in African children and commonly involves the jaw and kidneys. The sporadic (nonendemic) form accounts for 1% to 2% of all lymphomas in the United States and Western Europe and usually has an abdominal presentation. The immunodeficiency-associated form is commonly seen in HIV patients with a relatively preserved CD4 cell count.

Patients typically present with rapidly growing masses and tumor lysis syndrome. CNS and bone marrow involvement are common. Burkitt lymphoma cells are high-grade, rapidly proliferating medium-sized cells with a monomorphic appearance. Biopsies show a classic histological appearance known as a “starry sky pattern” due to benign macrophages engulfing debris resulting from apoptosis. It is derived from a germinal center B cell and has distinct oncogenic pathways. Translocations such as t(8;14), t(2;8) or t(8;22) juxtapose the MYC locus with immunoglobulin heavy or light chain loci and result in MYC overexpression. Burkitt lymphoma is typically CD10-positive and BCL-2-negative, with a MYC translocation and a proliferation rate greater than 95%.

With conventional NHL regimens, Burkitt lymphoma had a poor prognosis, with complete remission in the 30% to 70% range and low rates of long-term remission. With the introduction of short-term, dose-intensive, multiagent chemotherapy regimens (adapted from pediatric acute lymphoblastic leukemia [ALL] regimens), the complete remission rate improved to 60% to 90% [107]. Early stage disease (localized or completely resected intra-abdominal disease) can have complete remission rates of 100%, with 2- to 5-year freedom-from-progression rates of 95%. CNS prophylaxis, including high-dose methotrexate, high-dose cytarabine, and intrathecal chemotherapy, is a standard component of Burkitt lymphoma regimens (CNS relapse rates can reach 50% without prophylactic therapy). Crucially, relapse after 1 to 2 years is very rare following complete response to induction therapy. Classically, several intensive regimens have been used for Burkitt lymphoma. In recent years, the most commonly used regimens have been the modified Magrath regimen of R-CODOX-M/IVAC and R-hyperCVAD. DA-EPOCH-R has also been used, typically for older, more frail, or HIV-positive patients. However, at the American Society of Hematology 2017 annual meeting, results from the NCI 9177 trial were presented which validated, in a prospective multi-center fashion, the use of DA-EPOCH-R in all Burkitt lymphoma patients [108]. In NCI 9177, low-risk patients (defined as normal LDH, ECOG performance score 0 or 1, ≤ stage II, and no tumor lesion > 7 cm) received 2 cycles of DA-EPOCH-R without intrathecal therapy followed by PET. If interim PET was negative, low-risk patients then received 1 more cycle of DA-EPOCH-R. High-risk patients with negative brain MRI and CSF cytology/flow cytometry received 2 cycles of DA-EPOCH-R with intrathecal therapy (2 doses per cycle) followed by PET. Unless interim PET showed progression, high-risk patients received 4 additional cycles of DA-EPOCH-R including methotrexate 12 mg intrathecally on days 1 and 5 (8 total doses). With a median follow-up of 36 months, this regimen resulted in an EFS of 85.7%. As expected, patients with CNS, marrow, or peripheral blood involvement fared worse. For those without CNS, marrow, or peripheral blood involvement, the results were excellent, with an EFS of 94.6% compared to 62.8% for those with CNS, bone marrow, or blood involvement at diagnosis.

Although no standard of care has been defined, patients with relapsed/refractory Burkitt lymphoma are often given standard second-line aggressive NHL regimens (eg, R-ICE); for those with chemosensitive disease, auto- or allo-HCT is often pursued, with long-term remissions possible following HCT [109].

Lymphoblastic Lymphoma

Lymphoblastic lymphoma (LBL) is a rare disease postulated to arise from precursor B or T lymphoblasts at varying stages of differentiation. Accounting for approximately 2% of all NHLs, 85% to 90% of all cases have a T-cell phenotype, while B-cell LBL comprises approximately 10% to 15% of cases. LBL and ALL are thought to represent the same disease entity, but LBL has been arbitrarily defined as cases with lymph node or mediastinal disease. Those with significant (> 25%) bone marrow or peripheral blood involvement are classified as ALL.

Precursor T-cell LBL patients are usually adolescent and young males who commonly present with a mediastinal mass and peripheral lymphadenopathy. Precursor B-cell LBL patients are usually older (median age 39 years) with peripheral lymphadenopathy and extranodal involvement. Mediastinal involvement with B-cell LBL is uncommon, and there is no male predominance. LBL has a propensity for dissemination to the bone marrow and CNS.

Morphologically, the tumor cells are medium sized, with a scant cytoplasm and finely dispersed chromatin. Mitotic features and apoptotic bodies are present since it is a high-grade malignancy. The lymphoblasts are typically positive for CD7 and either surface or cytoplasmic CD3. Terminal deoxynucleotidyl transferase expression is a defining feature. Other markers such as CD19, CD22, CD20, CD79a, CD45, and CD10 are variably expressed. Poor prognostic factors in T-cell LBL are female gender, age greater than 35 years, complex cytogenetics, and lack of a matched sibling donor.

Regimens for LBL are based on dose-dense, multi-agent protocols used in ALL. Most of these regimens are characterized by intensive remission-induction chemotherapy, CNS prophylaxis, a phase of consolidation therapy, and a prolonged maintenance phase, often lasting for 12 to 18 months with long-term DFS rates of 40% to 70% [110,111]. High-dose therapy with auto-HCT or allo-HCT in first complete response has been evaluated in an attempt to reduce the incidence of relapse [112]. However, the intensity of primary chemotherapy appears to be a stronger determinant of long-term survival than the use of HCT as consolidation. As a result, HCT is not routinely applied to patients in first complete remission following modern induction regimens. After relapse, prognosis is poor, with median survival rates of 6 to 9 months with conventional chemotherapy, although long-term survival rates of 30% and 20%, respectively, are reported after HCT in relapsed and primary refractory disease [113].

Treatment options in relapsed disease are limited. Nelarabine can produce responses in up to 40% of relapsed/refractory LBL/ALL patients [114]. For the minority of LBL patients with a B-cell phenotype, emerging options for relapsed/refractory LBL/ALL such as inotuzumab, blinatumomab, or anti-CD19 CAR T-cell therapy should be considered. These are not options for the majority who have a T-cell phenotype, and treatment options for these patients are limited to conventional relapsed/refractory ALL and aggressive NHL regimens.

Summary

Aggressive NHLs are characterized by rapid clinical progression without therapy. However, a significant proportion of patients are cured with appropriate combination chemotherapy or combined modality (chemotherapy + RT) regimens. In contrast, the indolent lymphomas have a relatively good prognosis (median survival of 10 years or longer) but usually are not curable in advanced clinical stages. Overall 5-year survival for aggressive NHLs with current treatment is approximately 50% to 60%, with relapses typically occurring within the first 5 years. Treatment strategies for relapsed patients offer some potential for cure; however, clinical trial participation should be encouraged whenever possible to investigate new approaches for improving outcomes in this patient population.

Corresponding author: Timothy S. Fenske, MD, Division of Hematology & Oncology, Medical College of Wisconsin, 9200 W. Wisconsin Ave., Milwaukee, WI 53226.