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The Diagnosis: Livedoid Vasculopathy

Livedoid vasculopathy (LV) is a rare cutaneous disorder that most commonly affects the lower legs. It has an estimated incidence of 1 case per 100,000 per year and predominantly affects women.¹ The disease pathogenesis is not fully understood but is thought to involve thrombosis and occlusion of dermal vessels resulting in tissue hypoxia.² Both inherited and acquired thrombophilic conditions frequently are seen in patients with LV.^3,4 Livedoid vasculopathy also has been described as idiopathic⁵ and is associated with immune complex deposition.⁶ However, the number of cases of idiopathic LV may be overestimated; as technological advancements to detect coagulation abnormalities improve, it is hypothesized that this entity will be identified less often.^2,4

Livedoid vasculopathy has been described in the literature using the term PPURPLE (painful purpuric ulcers with reticular pattern of lower extremities).⁷ The triad of livedo racemosa, recurrent painful ulcerations, and residual healing with atrophie blanche characterizes the clinical manifestations of LV; however, all 3 characteristics do not need to appear simultaneously for a diagnosis to be made. The condition has a chronic course with spontaneous remissions and exacerbations. Episodic ulcerations occur, especially in the summertime, and heal slowly, leaving behind atrophic, porcelain white, stellate-shaped scars called atrophie blanche. Livedo racemosa also may be seen in Sneddon syndrome; however, these patients experience neurologic symptoms secondary to cerebrovascular occlusion. In contrast to livedo racemosa, acquired livedo reticularis represents a physiologic hypoperfusion pattern that occurs in response to cold exposure.⁸ A localized sharp pain, known as angina cutis, typically precedes the clinical symptom of painful ulcerations.⁹ Atrophie blanche once was thought to be specific to LV but has been seen in other diseases such as systemic lupus erythematosus and chronic venous insufficiency.²

The diagnosis of LV is based on identification of characteristic clinical features and skin biopsy. In almost all biopsy specimens, histopathology reveals fibrinoid occlusion of vessels in the superficial and mid dermis.⁴ Other findings may include epidermal necrosis and vessel wall hyalinization and infarction² (Figure). Because LV is commonly misdiagnosed as vasculitis, the absence of hallmark features of vasculitis such as neutrophilic infiltrate of blood vessel walls and fibrinoid necrosis suggest the diagnosis. Extensive laboratory evaluation for inherited and acquired coagulation abnormalities should be performed.

Treatment of LV is difficult, as there is currently no consensus on optimal therapy. The mainstay of therapy is to reduce pain, prevent infection, and reduce ulceration and development of atrophie blanche. Underlying causes should be identified and appropriately treated. Because the primary pathogenesis of LV is considered to be a hypercoagulable state, first-line treatment often includes therapies to enhance blood flow and prevent thrombosis such as smoking cessation, antiplatelet therapy, and pentoxifylline. Vasodilating agents, anti-inflammatory agents, anticoagulation, and fibrinolytic therapy also have been used with varying degrees of success.⁷

The Diagnosis: Livedoid Vasculopathy

Livedoid vasculopathy (LV) is a rare cutaneous disorder that most commonly affects the lower legs. It has an estimated incidence of 1 case per 100,000 per year and predominantly affects women.¹ The disease pathogenesis is not fully understood but is thought to involve thrombosis and occlusion of dermal vessels resulting in tissue hypoxia.² Both inherited and acquired thrombophilic conditions frequently are seen in patients with LV.^3,4 Livedoid vasculopathy also has been described as idiopathic⁵ and is associated with immune complex deposition.⁶ However, the number of cases of idiopathic LV may be overestimated; as technological advancements to detect coagulation abnormalities improve, it is hypothesized that this entity will be identified less often.^2,4

Livedoid vasculopathy has been described in the literature using the term PPURPLE (painful purpuric ulcers with reticular pattern of lower extremities).⁷ The triad of livedo racemosa, recurrent painful ulcerations, and residual healing with atrophie blanche characterizes the clinical manifestations of LV; however, all 3 characteristics do not need to appear simultaneously for a diagnosis to be made. The condition has a chronic course with spontaneous remissions and exacerbations. Episodic ulcerations occur, especially in the summertime, and heal slowly, leaving behind atrophic, porcelain white, stellate-shaped scars called atrophie blanche. Livedo racemosa also may be seen in Sneddon syndrome; however, these patients experience neurologic symptoms secondary to cerebrovascular occlusion. In contrast to livedo racemosa, acquired livedo reticularis represents a physiologic hypoperfusion pattern that occurs in response to cold exposure.⁸ A localized sharp pain, known as angina cutis, typically precedes the clinical symptom of painful ulcerations.⁹ Atrophie blanche once was thought to be specific to LV but has been seen in other diseases such as systemic lupus erythematosus and chronic venous insufficiency.²

The diagnosis of LV is based on identification of characteristic clinical features and skin biopsy. In almost all biopsy specimens, histopathology reveals fibrinoid occlusion of vessels in the superficial and mid dermis.⁴ Other findings may include epidermal necrosis and vessel wall hyalinization and infarction² (Figure). Because LV is commonly misdiagnosed as vasculitis, the absence of hallmark features of vasculitis such as neutrophilic infiltrate of blood vessel walls and fibrinoid necrosis suggest the diagnosis. Extensive laboratory evaluation for inherited and acquired coagulation abnormalities should be performed.

Treatment of LV is difficult, as there is currently no consensus on optimal therapy. The mainstay of therapy is to reduce pain, prevent infection, and reduce ulceration and development of atrophie blanche. Underlying causes should be identified and appropriately treated. Because the primary pathogenesis of LV is considered to be a hypercoagulable state, first-line treatment often includes therapies to enhance blood flow and prevent thrombosis such as smoking cessation, antiplatelet therapy, and pentoxifylline. Vasodilating agents, anti-inflammatory agents, anticoagulation, and fibrinolytic therapy also have been used with varying degrees of success.⁷

The Diagnosis: Livedoid Vasculopathy

Livedoid vasculopathy (LV) is a rare cutaneous disorder that most commonly affects the lower legs. It has an estimated incidence of 1 case per 100,000 per year and predominantly affects women.¹ The disease pathogenesis is not fully understood but is thought to involve thrombosis and occlusion of dermal vessels resulting in tissue hypoxia.² Both inherited and acquired thrombophilic conditions frequently are seen in patients with LV.^3,4 Livedoid vasculopathy also has been described as idiopathic⁵ and is associated with immune complex deposition.⁶ However, the number of cases of idiopathic LV may be overestimated; as technological advancements to detect coagulation abnormalities improve, it is hypothesized that this entity will be identified less often.^2,4

Livedoid vasculopathy has been described in the literature using the term PPURPLE (painful purpuric ulcers with reticular pattern of lower extremities).⁷ The triad of livedo racemosa, recurrent painful ulcerations, and residual healing with atrophie blanche characterizes the clinical manifestations of LV; however, all 3 characteristics do not need to appear simultaneously for a diagnosis to be made. The condition has a chronic course with spontaneous remissions and exacerbations. Episodic ulcerations occur, especially in the summertime, and heal slowly, leaving behind atrophic, porcelain white, stellate-shaped scars called atrophie blanche. Livedo racemosa also may be seen in Sneddon syndrome; however, these patients experience neurologic symptoms secondary to cerebrovascular occlusion. In contrast to livedo racemosa, acquired livedo reticularis represents a physiologic hypoperfusion pattern that occurs in response to cold exposure.⁸ A localized sharp pain, known as angina cutis, typically precedes the clinical symptom of painful ulcerations.⁹ Atrophie blanche once was thought to be specific to LV but has been seen in other diseases such as systemic lupus erythematosus and chronic venous insufficiency.²

The diagnosis of LV is based on identification of characteristic clinical features and skin biopsy. In almost all biopsy specimens, histopathology reveals fibrinoid occlusion of vessels in the superficial and mid dermis.⁴ Other findings may include epidermal necrosis and vessel wall hyalinization and infarction² (Figure). Because LV is commonly misdiagnosed as vasculitis, the absence of hallmark features of vasculitis such as neutrophilic infiltrate of blood vessel walls and fibrinoid necrosis suggest the diagnosis. Extensive laboratory evaluation for inherited and acquired coagulation abnormalities should be performed.

Treatment of LV is difficult, as there is currently no consensus on optimal therapy. The mainstay of therapy is to reduce pain, prevent infection, and reduce ulceration and development of atrophie blanche. Underlying causes should be identified and appropriately treated. Because the primary pathogenesis of LV is considered to be a hypercoagulable state, first-line treatment often includes therapies to enhance blood flow and prevent thrombosis such as smoking cessation, antiplatelet therapy, and pentoxifylline. Vasodilating agents, anti-inflammatory agents, anticoagulation, and fibrinolytic therapy also have been used with varying degrees of success.⁷

The Diagnosis: Radiation-Associated Angiosarcoma

At the time of presentation, a 4-mm lesional punch biopsy was obtained (Figure), which revealed an epithelioid neoplasm within the dermis expressing CD31 and CD34, and staining negatively for S-100, CD45, and estrogen and progesterone receptors. The histologic and immunophenotypic findings were compatible with the diagnosis of angiosarcoma. Given the patient’s history of radiation for breast carcinoma several years ago, this tumor was consistent with radiation-associated angiosarcoma (RAAS).

Development of secondary angiosarcoma has been linked to both prior radiation (RAAS) and chronic lymphedema (Stewart-Treves syndrome).¹ Radiation-associated angiosarcoma is defined as a “pathologically confirmed breast or chest wall angiosarcoma arising within a previously irradiated field.”² The incidence of RAAS is estimated to be 0.9 per 1000 individuals following radiation treatment of breast cancer over the subsequent 15 years and a mean time from radiation to development of 7 years.¹ Incidence is expected to increase in the future due to improved likelihood of surviving early-stage breast carcinoma and the increased use of external beam radiation therapy for management of breast cancer.

Differentiating between primary and secondary angiosarcoma of the breast is important. Although primary breast angiosarcoma usually arises in women aged 30 to 40 years, RAAS tends to arise in older women (mean age, 68 years) and is seen only in those women with prior radiation.² Additionally, high-level amplification of MYC, a known photo-oncogene, on chromosome 8 is a key genetic alteration of RAAS that helps to distinguish it from primary angiosarcoma, though this variance may be present in only half of RAAS cases.³ Immunohistochemical analysis of tumor cells for MYC expression correlates well with this amplification and also is helpful in distinguishing atypical vascular lesions from RAAS.⁴ Atypical vascular lesions, similar to RAAS, occur years after radiation exposure and may have a similar clinical presentation. Atypical vascular lesions do not progress to angiosarcoma in reported cases, but clinical and histologic overlap with RAAS make the diagnosis difficult.⁵ In these cases, analysis with fluorescence in situ hybridization or immunohistochemistry for the MYC amplification is important to differentiate these tumors.⁶

At the time of presentation, the majority of patients with RAAS of the breast have localized disease, often with a variable presentation. In all known cases, there have been skin changes present, emphasizing the importance of both patient and clinician vigilance on a regular basis in at-risk individuals. In one study, the most common presentation was breast ecchymosis, which was observed in 55% of patients.⁷ These lesions involve the dermis and are commonly mistaken for benign conditions such as infection or hemorrhage.² In 2 other studies, RAAS most often manifested as a skin nodule or apparent tumor, closely followed by either a rash or bruiselike presentation.^1,2

The overall recommendation for management of patients with ecchymotic skin lesions in previously irradiated regions is to obtain a biopsy specimen for tissue diagnosis. Although there is no standard of care for the management of RAAS, a multidisciplinary approach involving specialists from oncology, surgical oncology, and radiation oncology is recommended. Most often, radical surgery encompassing both the breast parenchyma and the at-risk radiated skin is performed. Extensive surgery has demonstrated the best survival benefits compared to mastectomy alone.⁷ Chemotherapeutics also may be used as adjuncts to surgery, which have been determined to decrease local recurrence rates but have no proven survival benefits.² Adverse prognostic factors for survival are tumor size greater than 10 cm and development of local and/or distant metastases.² Following the diagnosis of RAAS, our patient underwent radical mastectomy with adjuvant chemotherapy and remained disease free 6 months after surgery.

In summary, RAAS is a well-known, albeit relatively uncommon, consequence of radiation therapy. Dermatologists, oncologists, and primary care providers play an important role in recognizing this entity when evaluating patients with ecchymotic lesions as well as nodules or tumors within an irradiated field. Biopsy should be obtained promptly to prevent delay in diagnosis and to expedite referral to appropriate specialists for further evaluation and treatment.

The Diagnosis: Radiation-Associated Angiosarcoma

At the time of presentation, a 4-mm lesional punch biopsy was obtained (Figure), which revealed an epithelioid neoplasm within the dermis expressing CD31 and CD34, and staining negatively for S-100, CD45, and estrogen and progesterone receptors. The histologic and immunophenotypic findings were compatible with the diagnosis of angiosarcoma. Given the patient’s history of radiation for breast carcinoma several years ago, this tumor was consistent with radiation-associated angiosarcoma (RAAS).

Development of secondary angiosarcoma has been linked to both prior radiation (RAAS) and chronic lymphedema (Stewart-Treves syndrome).¹ Radiation-associated angiosarcoma is defined as a “pathologically confirmed breast or chest wall angiosarcoma arising within a previously irradiated field.”² The incidence of RAAS is estimated to be 0.9 per 1000 individuals following radiation treatment of breast cancer over the subsequent 15 years and a mean time from radiation to development of 7 years.¹ Incidence is expected to increase in the future due to improved likelihood of surviving early-stage breast carcinoma and the increased use of external beam radiation therapy for management of breast cancer.

Differentiating between primary and secondary angiosarcoma of the breast is important. Although primary breast angiosarcoma usually arises in women aged 30 to 40 years, RAAS tends to arise in older women (mean age, 68 years) and is seen only in those women with prior radiation.² Additionally, high-level amplification of MYC, a known photo-oncogene, on chromosome 8 is a key genetic alteration of RAAS that helps to distinguish it from primary angiosarcoma, though this variance may be present in only half of RAAS cases.³ Immunohistochemical analysis of tumor cells for MYC expression correlates well with this amplification and also is helpful in distinguishing atypical vascular lesions from RAAS.⁴ Atypical vascular lesions, similar to RAAS, occur years after radiation exposure and may have a similar clinical presentation. Atypical vascular lesions do not progress to angiosarcoma in reported cases, but clinical and histologic overlap with RAAS make the diagnosis difficult.⁵ In these cases, analysis with fluorescence in situ hybridization or immunohistochemistry for the MYC amplification is important to differentiate these tumors.⁶

At the time of presentation, the majority of patients with RAAS of the breast have localized disease, often with a variable presentation. In all known cases, there have been skin changes present, emphasizing the importance of both patient and clinician vigilance on a regular basis in at-risk individuals. In one study, the most common presentation was breast ecchymosis, which was observed in 55% of patients.⁷ These lesions involve the dermis and are commonly mistaken for benign conditions such as infection or hemorrhage.² In 2 other studies, RAAS most often manifested as a skin nodule or apparent tumor, closely followed by either a rash or bruiselike presentation.^1,2

The overall recommendation for management of patients with ecchymotic skin lesions in previously irradiated regions is to obtain a biopsy specimen for tissue diagnosis. Although there is no standard of care for the management of RAAS, a multidisciplinary approach involving specialists from oncology, surgical oncology, and radiation oncology is recommended. Most often, radical surgery encompassing both the breast parenchyma and the at-risk radiated skin is performed. Extensive surgery has demonstrated the best survival benefits compared to mastectomy alone.⁷ Chemotherapeutics also may be used as adjuncts to surgery, which have been determined to decrease local recurrence rates but have no proven survival benefits.² Adverse prognostic factors for survival are tumor size greater than 10 cm and development of local and/or distant metastases.² Following the diagnosis of RAAS, our patient underwent radical mastectomy with adjuvant chemotherapy and remained disease free 6 months after surgery.

In summary, RAAS is a well-known, albeit relatively uncommon, consequence of radiation therapy. Dermatologists, oncologists, and primary care providers play an important role in recognizing this entity when evaluating patients with ecchymotic lesions as well as nodules or tumors within an irradiated field. Biopsy should be obtained promptly to prevent delay in diagnosis and to expedite referral to appropriate specialists for further evaluation and treatment.

The Diagnosis: Radiation-Associated Angiosarcoma

At the time of presentation, a 4-mm lesional punch biopsy was obtained (Figure), which revealed an epithelioid neoplasm within the dermis expressing CD31 and CD34, and staining negatively for S-100, CD45, and estrogen and progesterone receptors. The histologic and immunophenotypic findings were compatible with the diagnosis of angiosarcoma. Given the patient’s history of radiation for breast carcinoma several years ago, this tumor was consistent with radiation-associated angiosarcoma (RAAS).

Development of secondary angiosarcoma has been linked to both prior radiation (RAAS) and chronic lymphedema (Stewart-Treves syndrome).¹ Radiation-associated angiosarcoma is defined as a “pathologically confirmed breast or chest wall angiosarcoma arising within a previously irradiated field.”² The incidence of RAAS is estimated to be 0.9 per 1000 individuals following radiation treatment of breast cancer over the subsequent 15 years and a mean time from radiation to development of 7 years.¹ Incidence is expected to increase in the future due to improved likelihood of surviving early-stage breast carcinoma and the increased use of external beam radiation therapy for management of breast cancer.

Differentiating between primary and secondary angiosarcoma of the breast is important. Although primary breast angiosarcoma usually arises in women aged 30 to 40 years, RAAS tends to arise in older women (mean age, 68 years) and is seen only in those women with prior radiation.² Additionally, high-level amplification of MYC, a known photo-oncogene, on chromosome 8 is a key genetic alteration of RAAS that helps to distinguish it from primary angiosarcoma, though this variance may be present in only half of RAAS cases.³ Immunohistochemical analysis of tumor cells for MYC expression correlates well with this amplification and also is helpful in distinguishing atypical vascular lesions from RAAS.⁴ Atypical vascular lesions, similar to RAAS, occur years after radiation exposure and may have a similar clinical presentation. Atypical vascular lesions do not progress to angiosarcoma in reported cases, but clinical and histologic overlap with RAAS make the diagnosis difficult.⁵ In these cases, analysis with fluorescence in situ hybridization or immunohistochemistry for the MYC amplification is important to differentiate these tumors.⁶

At the time of presentation, the majority of patients with RAAS of the breast have localized disease, often with a variable presentation. In all known cases, there have been skin changes present, emphasizing the importance of both patient and clinician vigilance on a regular basis in at-risk individuals. In one study, the most common presentation was breast ecchymosis, which was observed in 55% of patients.⁷ These lesions involve the dermis and are commonly mistaken for benign conditions such as infection or hemorrhage.² In 2 other studies, RAAS most often manifested as a skin nodule or apparent tumor, closely followed by either a rash or bruiselike presentation.^1,2

The overall recommendation for management of patients with ecchymotic skin lesions in previously irradiated regions is to obtain a biopsy specimen for tissue diagnosis. Although there is no standard of care for the management of RAAS, a multidisciplinary approach involving specialists from oncology, surgical oncology, and radiation oncology is recommended. Most often, radical surgery encompassing both the breast parenchyma and the at-risk radiated skin is performed. Extensive surgery has demonstrated the best survival benefits compared to mastectomy alone.⁷ Chemotherapeutics also may be used as adjuncts to surgery, which have been determined to decrease local recurrence rates but have no proven survival benefits.² Adverse prognostic factors for survival are tumor size greater than 10 cm and development of local and/or distant metastases.² Following the diagnosis of RAAS, our patient underwent radical mastectomy with adjuvant chemotherapy and remained disease free 6 months after surgery.

In summary, RAAS is a well-known, albeit relatively uncommon, consequence of radiation therapy. Dermatologists, oncologists, and primary care providers play an important role in recognizing this entity when evaluating patients with ecchymotic lesions as well as nodules or tumors within an irradiated field. Biopsy should be obtained promptly to prevent delay in diagnosis and to expedite referral to appropriate specialists for further evaluation and treatment.

The Diagnosis: Atypical Mycobacterial Infection

Punch biopsy specimens demonstrated necrotizing granulomatous inflammation in the dermis and subcutis (Figure). Special staining for microorganisms was negative. Tissue culture grew Mycobacterium avium-intracellulare (MAI). The patient began treatment with azithromycin, ethambutol, and rifabutin. Tissue susceptibilities later showed resistance to rifabutin and sensitivity to clarithromycin, moxifloxacin, and clofazimine. She subsequently was switched to azithromycin, clofazimine, and moxifloxacin with good response.

Mycobacterium avium-intracellulare is a slow-growing, nonchromogenic, atypical mycobacteria. Although ubiquitous, it tends to only cause serious infection in the setting of immunosuppression. Transmission usually is through the respiratory or gastrointestinal tract.¹ Skin infections with MAI are uncommon and usually are secondary to seeding from disseminated infection or from direct inoculation.²

The clinical presentations of primary cutaneous MAI are myriad, including an isolated red nodule, multiple ulcers, abscesses, draining sinuses, facial nodules, granulomatous plaques, and panniculitis.^2,3 Of 3 reported cases of primary cutaneous MAI in the form of sporotrichoid lesions, 2 involved patients with AIDS² and 1 involved a cardiac transplant recipient.⁴

Cutaneous MAI is typically diagnosed with skin biopsy and tissue culture. Tissue culture is critical for determining the specific mycobacterial species and antibiotic susceptibilities. Polymerase chain reaction has been utilized to rapidly diagnose cutaneous MAI infection from an acid-fast bacilli–positive tissue sample in which the tissue culture was negative.⁵

Recommended treatment protocols for MAI involve multidrug regimens because of the intrinsic resistance of MAI and the concern for development of resistance with monotherapy.² No definitive guidelines exist for treatment of primary cutaneous MAI infections. However, regimens for the treatment of pulmonary infection that also have been successfully utilized for cutaneous infection include a macrolide, ethambutol, and a rifamycin.⁶ Clinicians should be aware of MAI as a cause of primary cutaneous infections presenting as lymphocutaneous suppurative nodules and ulcerations.

The Diagnosis: Atypical Mycobacterial Infection

Punch biopsy specimens demonstrated necrotizing granulomatous inflammation in the dermis and subcutis (Figure). Special staining for microorganisms was negative. Tissue culture grew Mycobacterium avium-intracellulare (MAI). The patient began treatment with azithromycin, ethambutol, and rifabutin. Tissue susceptibilities later showed resistance to rifabutin and sensitivity to clarithromycin, moxifloxacin, and clofazimine. She subsequently was switched to azithromycin, clofazimine, and moxifloxacin with good response.

Mycobacterium avium-intracellulare is a slow-growing, nonchromogenic, atypical mycobacteria. Although ubiquitous, it tends to only cause serious infection in the setting of immunosuppression. Transmission usually is through the respiratory or gastrointestinal tract.¹ Skin infections with MAI are uncommon and usually are secondary to seeding from disseminated infection or from direct inoculation.²

The clinical presentations of primary cutaneous MAI are myriad, including an isolated red nodule, multiple ulcers, abscesses, draining sinuses, facial nodules, granulomatous plaques, and panniculitis.^2,3 Of 3 reported cases of primary cutaneous MAI in the form of sporotrichoid lesions, 2 involved patients with AIDS² and 1 involved a cardiac transplant recipient.⁴

Cutaneous MAI is typically diagnosed with skin biopsy and tissue culture. Tissue culture is critical for determining the specific mycobacterial species and antibiotic susceptibilities. Polymerase chain reaction has been utilized to rapidly diagnose cutaneous MAI infection from an acid-fast bacilli–positive tissue sample in which the tissue culture was negative.⁵

Recommended treatment protocols for MAI involve multidrug regimens because of the intrinsic resistance of MAI and the concern for development of resistance with monotherapy.² No definitive guidelines exist for treatment of primary cutaneous MAI infections. However, regimens for the treatment of pulmonary infection that also have been successfully utilized for cutaneous infection include a macrolide, ethambutol, and a rifamycin.⁶ Clinicians should be aware of MAI as a cause of primary cutaneous infections presenting as lymphocutaneous suppurative nodules and ulcerations.

The Diagnosis: Atypical Mycobacterial Infection

Punch biopsy specimens demonstrated necrotizing granulomatous inflammation in the dermis and subcutis (Figure). Special staining for microorganisms was negative. Tissue culture grew Mycobacterium avium-intracellulare (MAI). The patient began treatment with azithromycin, ethambutol, and rifabutin. Tissue susceptibilities later showed resistance to rifabutin and sensitivity to clarithromycin, moxifloxacin, and clofazimine. She subsequently was switched to azithromycin, clofazimine, and moxifloxacin with good response.

Mycobacterium avium-intracellulare is a slow-growing, nonchromogenic, atypical mycobacteria. Although ubiquitous, it tends to only cause serious infection in the setting of immunosuppression. Transmission usually is through the respiratory or gastrointestinal tract.¹ Skin infections with MAI are uncommon and usually are secondary to seeding from disseminated infection or from direct inoculation.²

The clinical presentations of primary cutaneous MAI are myriad, including an isolated red nodule, multiple ulcers, abscesses, draining sinuses, facial nodules, granulomatous plaques, and panniculitis.^2,3 Of 3 reported cases of primary cutaneous MAI in the form of sporotrichoid lesions, 2 involved patients with AIDS² and 1 involved a cardiac transplant recipient.⁴

Cutaneous MAI is typically diagnosed with skin biopsy and tissue culture. Tissue culture is critical for determining the specific mycobacterial species and antibiotic susceptibilities. Polymerase chain reaction has been utilized to rapidly diagnose cutaneous MAI infection from an acid-fast bacilli–positive tissue sample in which the tissue culture was negative.⁵

Recommended treatment protocols for MAI involve multidrug regimens because of the intrinsic resistance of MAI and the concern for development of resistance with monotherapy.² No definitive guidelines exist for treatment of primary cutaneous MAI infections. However, regimens for the treatment of pulmonary infection that also have been successfully utilized for cutaneous infection include a macrolide, ethambutol, and a rifamycin.⁶ Clinicians should be aware of MAI as a cause of primary cutaneous infections presenting as lymphocutaneous suppurative nodules and ulcerations.

The Diagnosis: Temporal Triangular Alopecia

Temporal triangular alopecia (TTA), also known as congenital triangular alopecia, was first described in the early 1900s.¹ It presents clinically as a triangular-shaped area of nonscarring alopecia either unilaterally or bilaterally. Limited clinical data suggest that most unilateral cases are on the left frontotemporal region of the scalp. In bilateral cases, there may be asymmetry in size of the area involved.² Dermatoscopically, TTA is characterized by decreased terminal hair follicle density as well as the presence of vellus hairs with an absence of inflammation.³ The majority of TTA is noted between birth and 6 years of life with the areas staying stable thereafter. Large areas of TTA may suggest cerebello-trigeminal-dermal dysplasia (Gomez-Lopez-Hernandez syndrome), a rare neurocutaneous syndrome characterized by rhombencephalosynapsis, trigeminal anesthesia, and parietooccipital alopecia (Online Mendelian Inheritance in Man 601853).⁴ Although TTA is largely idiopathic, it has been suggested that the trait may be paradominant, whereby a postzygotic loss of the wild-type allele in a heterozygotic state causes triangular alopecia and reflects hamartomatous mosaicism.⁵ It also is an important mimicker of alopecia areata. Correct identification prevents unnecessary treatment to the areas of the scalp. Hair restoration surgery has been reported as a tool to treat this disorder.⁶

The Diagnosis: Temporal Triangular Alopecia

Temporal triangular alopecia (TTA), also known as congenital triangular alopecia, was first described in the early 1900s.¹ It presents clinically as a triangular-shaped area of nonscarring alopecia either unilaterally or bilaterally. Limited clinical data suggest that most unilateral cases are on the left frontotemporal region of the scalp. In bilateral cases, there may be asymmetry in size of the area involved.² Dermatoscopically, TTA is characterized by decreased terminal hair follicle density as well as the presence of vellus hairs with an absence of inflammation.³ The majority of TTA is noted between birth and 6 years of life with the areas staying stable thereafter. Large areas of TTA may suggest cerebello-trigeminal-dermal dysplasia (Gomez-Lopez-Hernandez syndrome), a rare neurocutaneous syndrome characterized by rhombencephalosynapsis, trigeminal anesthesia, and parietooccipital alopecia (Online Mendelian Inheritance in Man 601853).⁴ Although TTA is largely idiopathic, it has been suggested that the trait may be paradominant, whereby a postzygotic loss of the wild-type allele in a heterozygotic state causes triangular alopecia and reflects hamartomatous mosaicism.⁵ It also is an important mimicker of alopecia areata. Correct identification prevents unnecessary treatment to the areas of the scalp. Hair restoration surgery has been reported as a tool to treat this disorder.⁶

The Diagnosis: Temporal Triangular Alopecia

Temporal triangular alopecia (TTA), also known as congenital triangular alopecia, was first described in the early 1900s.¹ It presents clinically as a triangular-shaped area of nonscarring alopecia either unilaterally or bilaterally. Limited clinical data suggest that most unilateral cases are on the left frontotemporal region of the scalp. In bilateral cases, there may be asymmetry in size of the area involved.² Dermatoscopically, TTA is characterized by decreased terminal hair follicle density as well as the presence of vellus hairs with an absence of inflammation.³ The majority of TTA is noted between birth and 6 years of life with the areas staying stable thereafter. Large areas of TTA may suggest cerebello-trigeminal-dermal dysplasia (Gomez-Lopez-Hernandez syndrome), a rare neurocutaneous syndrome characterized by rhombencephalosynapsis, trigeminal anesthesia, and parietooccipital alopecia (Online Mendelian Inheritance in Man 601853).⁴ Although TTA is largely idiopathic, it has been suggested that the trait may be paradominant, whereby a postzygotic loss of the wild-type allele in a heterozygotic state causes triangular alopecia and reflects hamartomatous mosaicism.⁵ It also is an important mimicker of alopecia areata. Correct identification prevents unnecessary treatment to the areas of the scalp. Hair restoration surgery has been reported as a tool to treat this disorder.⁶

The Diagnosis: Trigeminal Trophic Syndrome

Trigeminal trophic syndrome (TTS) is a rare condition occurring after injury to the sensory roots of the trigeminal nerve. Trigeminal trophic syndrome was first described in 1933 by Loveman¹ as a complication of ablative treatment of trigeminal neuralgia; however, it has been observed with lesions to the central or peripheral nervous system that damage sensory components of the trigeminal nerve. In our patient, the cause was likely an infarction of the posterior inferior cerebellar artery, which supplies both the cerebellum and the trigeminal nuclei in the brain stem.

Other possible causes of TTS include injury from herpes zoster ophthalmicus; vertebrobasilar insufficiency; trauma; Mycobacterium leprae neuritis; spinal cord degeneration; syringobulbia; or tumors such as astrocytomas, meningiomas, and acoustic neuromas.² The most typical presenting manifestation is a unilateral, crescent-shaped ulceration of the nasal ala, specifically where cartilage is lacking.³ Less frequently, it affects the upper lip, cheeks, forehead, scalp, and ear. It characteristically spares the nasal tip, which derives sensory innervation from the medial branch of the anterior ethmoidal nerve.⁴ The affected dermatomal distribution can show anesthesia or paresthesia, promoting the urge to touch, pick, or rub the area.

Histology of the TTS lesion is nondiagnostic, usually showing a mixed dermal inflammation without evidence of infection, vasculitis, or malignancy. In our patient, Gram stain, Grocott-Gomori methenamine-silver stain, and immunohistochemical stains to rule out leukemia or lymphoma were all negative. In addition, flow cytometry of the forehead tissue also was normal. Tests for human immunodeficiency virus, herpes simplex virus types 1 and 2, hepatitis, syphilis, histoplasmosis, blastomycosis, coccidioides, and tuberculosis were negative.During the biopsy, the patient was noted to have anesthesia of the skin. He also admitted to facial manipulation and was noted to have blood and tissue under the fingernails on mornings when the lesion was left uncovered overnight.

Treatment of TTS often can be difficult, especially if patients do not admit to wound manipulation or if manipulation occurs during sleep. Prevention of further ulceration can sometimes be achieved by occlusive dressing alone with mupirocin. Physical barriers can be supplemented with medications such as amitriptyline, carbamazepine, diazepam, chlorpromazine, and gabapentin to attempt to reduce paresthesia.² Psychiatric consultation can sometimes be necessary and helpful.³ Additionally, negative pressure wound therapy has been used with success in the pediatric setting when digital manipulation is difficult to control.⁵ More aggressive treatments include transcutaneous electrical stimulation, stellate ganglionectomy, radiotherapy, and innervated rotation flaps.^6,7

In summary, recognition of this relatively rare cause of unilateral facial erosions is critical, both to prevent counterproductive treatments such as steroids and to initiate measures to prevent further trauma to the lesion.

The Diagnosis: Trigeminal Trophic Syndrome

Trigeminal trophic syndrome (TTS) is a rare condition occurring after injury to the sensory roots of the trigeminal nerve. Trigeminal trophic syndrome was first described in 1933 by Loveman¹ as a complication of ablative treatment of trigeminal neuralgia; however, it has been observed with lesions to the central or peripheral nervous system that damage sensory components of the trigeminal nerve. In our patient, the cause was likely an infarction of the posterior inferior cerebellar artery, which supplies both the cerebellum and the trigeminal nuclei in the brain stem.

Other possible causes of TTS include injury from herpes zoster ophthalmicus; vertebrobasilar insufficiency; trauma; Mycobacterium leprae neuritis; spinal cord degeneration; syringobulbia; or tumors such as astrocytomas, meningiomas, and acoustic neuromas.² The most typical presenting manifestation is a unilateral, crescent-shaped ulceration of the nasal ala, specifically where cartilage is lacking.³ Less frequently, it affects the upper lip, cheeks, forehead, scalp, and ear. It characteristically spares the nasal tip, which derives sensory innervation from the medial branch of the anterior ethmoidal nerve.⁴ The affected dermatomal distribution can show anesthesia or paresthesia, promoting the urge to touch, pick, or rub the area.

Histology of the TTS lesion is nondiagnostic, usually showing a mixed dermal inflammation without evidence of infection, vasculitis, or malignancy. In our patient, Gram stain, Grocott-Gomori methenamine-silver stain, and immunohistochemical stains to rule out leukemia or lymphoma were all negative. In addition, flow cytometry of the forehead tissue also was normal. Tests for human immunodeficiency virus, herpes simplex virus types 1 and 2, hepatitis, syphilis, histoplasmosis, blastomycosis, coccidioides, and tuberculosis were negative.During the biopsy, the patient was noted to have anesthesia of the skin. He also admitted to facial manipulation and was noted to have blood and tissue under the fingernails on mornings when the lesion was left uncovered overnight.

Treatment of TTS often can be difficult, especially if patients do not admit to wound manipulation or if manipulation occurs during sleep. Prevention of further ulceration can sometimes be achieved by occlusive dressing alone with mupirocin. Physical barriers can be supplemented with medications such as amitriptyline, carbamazepine, diazepam, chlorpromazine, and gabapentin to attempt to reduce paresthesia.² Psychiatric consultation can sometimes be necessary and helpful.³ Additionally, negative pressure wound therapy has been used with success in the pediatric setting when digital manipulation is difficult to control.⁵ More aggressive treatments include transcutaneous electrical stimulation, stellate ganglionectomy, radiotherapy, and innervated rotation flaps.^6,7

In summary, recognition of this relatively rare cause of unilateral facial erosions is critical, both to prevent counterproductive treatments such as steroids and to initiate measures to prevent further trauma to the lesion.

The Diagnosis: Trigeminal Trophic Syndrome

Trigeminal trophic syndrome (TTS) is a rare condition occurring after injury to the sensory roots of the trigeminal nerve. Trigeminal trophic syndrome was first described in 1933 by Loveman¹ as a complication of ablative treatment of trigeminal neuralgia; however, it has been observed with lesions to the central or peripheral nervous system that damage sensory components of the trigeminal nerve. In our patient, the cause was likely an infarction of the posterior inferior cerebellar artery, which supplies both the cerebellum and the trigeminal nuclei in the brain stem.

Other possible causes of TTS include injury from herpes zoster ophthalmicus; vertebrobasilar insufficiency; trauma; Mycobacterium leprae neuritis; spinal cord degeneration; syringobulbia; or tumors such as astrocytomas, meningiomas, and acoustic neuromas.² The most typical presenting manifestation is a unilateral, crescent-shaped ulceration of the nasal ala, specifically where cartilage is lacking.³ Less frequently, it affects the upper lip, cheeks, forehead, scalp, and ear. It characteristically spares the nasal tip, which derives sensory innervation from the medial branch of the anterior ethmoidal nerve.⁴ The affected dermatomal distribution can show anesthesia or paresthesia, promoting the urge to touch, pick, or rub the area.

Histology of the TTS lesion is nondiagnostic, usually showing a mixed dermal inflammation without evidence of infection, vasculitis, or malignancy. In our patient, Gram stain, Grocott-Gomori methenamine-silver stain, and immunohistochemical stains to rule out leukemia or lymphoma were all negative. In addition, flow cytometry of the forehead tissue also was normal. Tests for human immunodeficiency virus, herpes simplex virus types 1 and 2, hepatitis, syphilis, histoplasmosis, blastomycosis, coccidioides, and tuberculosis were negative.During the biopsy, the patient was noted to have anesthesia of the skin. He also admitted to facial manipulation and was noted to have blood and tissue under the fingernails on mornings when the lesion was left uncovered overnight.

Treatment of TTS often can be difficult, especially if patients do not admit to wound manipulation or if manipulation occurs during sleep. Prevention of further ulceration can sometimes be achieved by occlusive dressing alone with mupirocin. Physical barriers can be supplemented with medications such as amitriptyline, carbamazepine, diazepam, chlorpromazine, and gabapentin to attempt to reduce paresthesia.² Psychiatric consultation can sometimes be necessary and helpful.³ Additionally, negative pressure wound therapy has been used with success in the pediatric setting when digital manipulation is difficult to control.⁵ More aggressive treatments include transcutaneous electrical stimulation, stellate ganglionectomy, radiotherapy, and innervated rotation flaps.^6,7

In summary, recognition of this relatively rare cause of unilateral facial erosions is critical, both to prevent counterproductive treatments such as steroids and to initiate measures to prevent further trauma to the lesion.

The Diagnosis: Necrolytic Acral Erythema

Histopathologic analysis of a biopsy specimen from the right leg revealed an erosion with parakeratosis containing neutrophils and marked spongiosis favoring the upper layer of the epidermis with focal individual necrotic keratinocytes. In addition, there was a lymphocytic and neutrophilic exocytosis with edema of the papillary dermal papillae, mild papillary dermal fibrosis, and a mild perivascular lymphocytic infiltrate with neutrophils and occasional eosinophils. Clinicopathologic correlation led to a diagnosis of necrolytic acral erythema (NAE).

The patient was prescribed clobetasol propionate ointment 0.05% and oral zinc sulfate 220 mg twice daily but was initially noncompliant with the topical corticosteroid regimen. He did, however, initiate zinc supplementation, which was later increased to 220 mg 3 times daily. At 3-month follow-up, the lesions had nearly completely cleared (Figure) and the serum zinc level was within reference range at 81 μg/dL.

Necrolytic acral erythema is a rare dermatosis that was first described in 1996 by el Darouti and Abu el Ela¹ in a series of 7 Egyptian patients. Since then, most of the cases have reported concomitant hepatitis C virus (HCV) infection.² Necrolytic acral erythema classically presents with symmetric, well-defined, hyperkeratotic plaques in an acral distribution, typically on the dorsal aspect of the feet.^2,3 Lesions may involve the dorsal aspect of the toes and the lower legs, with less common involvement of the elbows, hands, and buttocks. Patients often report pruritus and/or burning.³

Abdallah et al⁴ proposed several stages of NAE development with erythematous papules with dusky eroded centers progressing to marginated, erythematous to violaceous, lichenified plaques. Over time, these lesions tend to thin with progressive hyperpigmentation.

Histologically, early findings of NAE include acanthosis with epidermal spongiosis and upper dermal perivascular dermatitis. Over time, lesions may exhibit psoriasiform hyperplasia with papillomatosis and parakeratosis, epidermal pallor, subcorneal pustules, vascular ectasia, papillary dermal inflammation, and necrotic keratinocytes. Minimal to moderate acanthosis with an inflammatory infiltrate may be observed later in disease progression.⁵

The differential diagnosis of NAE includes many benign inflammatory skin diseases. Given the acral/extensor distribution of hyperkeratotic lesions and psoriasiform pattern on histopathology, NAE initially may be misdiagnosed as psoriasis. Unlike psoriasis, however, NAE rarely involves palmoplantar skin or nails⁴ and may respond dramatically to treatment with zinc supplementation.^6,7 Necrolytic acral erythema also may be confused with other necrolytic erythemas, including necrolytic migratory erythema, acrodermatitis enteropathica, and pellagra. A deficiency of biotin or essential fatty acids also may mimic NAE. Necrolytic acral erythema can be distinguished from these entities based on its characteristic appearance and distribution, along with comorbid HCV infection.^2-4

Several reports of NAE have revealed an associated zinc deficiency.^2,8 The underlying pathophysiology of zinc deficiency in NAE has not been elucidated but is thought to be related to HCV infection.² Clinical improvement has been reported with zinc supplementation in patients with NAE at dosages of 220 mg twice daily, even in those with initial serum zinc levels within reference range.^6,7 Our patient was observed to have a low serum zinc level that dramatically improved with oral supplementation.

The recognition of this uncommon entity is critical for dermatologists and dermatopathologists, as NAE has been proposed as an early cutaneous marker of HCV and may prompt the initial diagnosis of HCV.^1-10 The severity of NAE has even been linked to HCV severity.^1,8 Treatment of HCV has cleared NAE in several cases,^4,10 implicating the virus in its pathogenesis. A proper workup for liver dysfunction and follow-up with an appropriate health care provider for HCV treatment is crucial. Our patient was encouraged to follow up with the hepatology department, as he had not been evaluated in several years.

The Diagnosis: Necrolytic Acral Erythema

Histopathologic analysis of a biopsy specimen from the right leg revealed an erosion with parakeratosis containing neutrophils and marked spongiosis favoring the upper layer of the epidermis with focal individual necrotic keratinocytes. In addition, there was a lymphocytic and neutrophilic exocytosis with edema of the papillary dermal papillae, mild papillary dermal fibrosis, and a mild perivascular lymphocytic infiltrate with neutrophils and occasional eosinophils. Clinicopathologic correlation led to a diagnosis of necrolytic acral erythema (NAE).

The patient was prescribed clobetasol propionate ointment 0.05% and oral zinc sulfate 220 mg twice daily but was initially noncompliant with the topical corticosteroid regimen. He did, however, initiate zinc supplementation, which was later increased to 220 mg 3 times daily. At 3-month follow-up, the lesions had nearly completely cleared (Figure) and the serum zinc level was within reference range at 81 μg/dL.

Necrolytic acral erythema is a rare dermatosis that was first described in 1996 by el Darouti and Abu el Ela¹ in a series of 7 Egyptian patients. Since then, most of the cases have reported concomitant hepatitis C virus (HCV) infection.² Necrolytic acral erythema classically presents with symmetric, well-defined, hyperkeratotic plaques in an acral distribution, typically on the dorsal aspect of the feet.^2,3 Lesions may involve the dorsal aspect of the toes and the lower legs, with less common involvement of the elbows, hands, and buttocks. Patients often report pruritus and/or burning.³

Abdallah et al⁴ proposed several stages of NAE development with erythematous papules with dusky eroded centers progressing to marginated, erythematous to violaceous, lichenified plaques. Over time, these lesions tend to thin with progressive hyperpigmentation.

Histologically, early findings of NAE include acanthosis with epidermal spongiosis and upper dermal perivascular dermatitis. Over time, lesions may exhibit psoriasiform hyperplasia with papillomatosis and parakeratosis, epidermal pallor, subcorneal pustules, vascular ectasia, papillary dermal inflammation, and necrotic keratinocytes. Minimal to moderate acanthosis with an inflammatory infiltrate may be observed later in disease progression.⁵

The differential diagnosis of NAE includes many benign inflammatory skin diseases. Given the acral/extensor distribution of hyperkeratotic lesions and psoriasiform pattern on histopathology, NAE initially may be misdiagnosed as psoriasis. Unlike psoriasis, however, NAE rarely involves palmoplantar skin or nails⁴ and may respond dramatically to treatment with zinc supplementation.^6,7 Necrolytic acral erythema also may be confused with other necrolytic erythemas, including necrolytic migratory erythema, acrodermatitis enteropathica, and pellagra. A deficiency of biotin or essential fatty acids also may mimic NAE. Necrolytic acral erythema can be distinguished from these entities based on its characteristic appearance and distribution, along with comorbid HCV infection.^2-4

Several reports of NAE have revealed an associated zinc deficiency.^2,8 The underlying pathophysiology of zinc deficiency in NAE has not been elucidated but is thought to be related to HCV infection.² Clinical improvement has been reported with zinc supplementation in patients with NAE at dosages of 220 mg twice daily, even in those with initial serum zinc levels within reference range.^6,7 Our patient was observed to have a low serum zinc level that dramatically improved with oral supplementation.

The recognition of this uncommon entity is critical for dermatologists and dermatopathologists, as NAE has been proposed as an early cutaneous marker of HCV and may prompt the initial diagnosis of HCV.^1-10 The severity of NAE has even been linked to HCV severity.^1,8 Treatment of HCV has cleared NAE in several cases,^4,10 implicating the virus in its pathogenesis. A proper workup for liver dysfunction and follow-up with an appropriate health care provider for HCV treatment is crucial. Our patient was encouraged to follow up with the hepatology department, as he had not been evaluated in several years.

The Diagnosis: Necrolytic Acral Erythema

Histopathologic analysis of a biopsy specimen from the right leg revealed an erosion with parakeratosis containing neutrophils and marked spongiosis favoring the upper layer of the epidermis with focal individual necrotic keratinocytes. In addition, there was a lymphocytic and neutrophilic exocytosis with edema of the papillary dermal papillae, mild papillary dermal fibrosis, and a mild perivascular lymphocytic infiltrate with neutrophils and occasional eosinophils. Clinicopathologic correlation led to a diagnosis of necrolytic acral erythema (NAE).

The patient was prescribed clobetasol propionate ointment 0.05% and oral zinc sulfate 220 mg twice daily but was initially noncompliant with the topical corticosteroid regimen. He did, however, initiate zinc supplementation, which was later increased to 220 mg 3 times daily. At 3-month follow-up, the lesions had nearly completely cleared (Figure) and the serum zinc level was within reference range at 81 μg/dL.

Necrolytic acral erythema is a rare dermatosis that was first described in 1996 by el Darouti and Abu el Ela¹ in a series of 7 Egyptian patients. Since then, most of the cases have reported concomitant hepatitis C virus (HCV) infection.² Necrolytic acral erythema classically presents with symmetric, well-defined, hyperkeratotic plaques in an acral distribution, typically on the dorsal aspect of the feet.^2,3 Lesions may involve the dorsal aspect of the toes and the lower legs, with less common involvement of the elbows, hands, and buttocks. Patients often report pruritus and/or burning.³

Abdallah et al⁴ proposed several stages of NAE development with erythematous papules with dusky eroded centers progressing to marginated, erythematous to violaceous, lichenified plaques. Over time, these lesions tend to thin with progressive hyperpigmentation.

Histologically, early findings of NAE include acanthosis with epidermal spongiosis and upper dermal perivascular dermatitis. Over time, lesions may exhibit psoriasiform hyperplasia with papillomatosis and parakeratosis, epidermal pallor, subcorneal pustules, vascular ectasia, papillary dermal inflammation, and necrotic keratinocytes. Minimal to moderate acanthosis with an inflammatory infiltrate may be observed later in disease progression.⁵

The differential diagnosis of NAE includes many benign inflammatory skin diseases. Given the acral/extensor distribution of hyperkeratotic lesions and psoriasiform pattern on histopathology, NAE initially may be misdiagnosed as psoriasis. Unlike psoriasis, however, NAE rarely involves palmoplantar skin or nails⁴ and may respond dramatically to treatment with zinc supplementation.^6,7 Necrolytic acral erythema also may be confused with other necrolytic erythemas, including necrolytic migratory erythema, acrodermatitis enteropathica, and pellagra. A deficiency of biotin or essential fatty acids also may mimic NAE. Necrolytic acral erythema can be distinguished from these entities based on its characteristic appearance and distribution, along with comorbid HCV infection.^2-4

Several reports of NAE have revealed an associated zinc deficiency.^2,8 The underlying pathophysiology of zinc deficiency in NAE has not been elucidated but is thought to be related to HCV infection.² Clinical improvement has been reported with zinc supplementation in patients with NAE at dosages of 220 mg twice daily, even in those with initial serum zinc levels within reference range.^6,7 Our patient was observed to have a low serum zinc level that dramatically improved with oral supplementation.

The recognition of this uncommon entity is critical for dermatologists and dermatopathologists, as NAE has been proposed as an early cutaneous marker of HCV and may prompt the initial diagnosis of HCV.^1-10 The severity of NAE has even been linked to HCV severity.^1,8 Treatment of HCV has cleared NAE in several cases,^4,10 implicating the virus in its pathogenesis. A proper workup for liver dysfunction and follow-up with an appropriate health care provider for HCV treatment is crucial. Our patient was encouraged to follow up with the hepatology department, as he had not been evaluated in several years.

The Diagnosis: Irritated Seborrheic Keratosis

Biopsies of one of the protruding papules and the underlying plaque were performed. The specimen from the papule showed hyperkeratosis, acanthosis, papillomatosis, and a flattened dermoepidermal junction with demarcated horizontal margin, which demonstrated apparent upward growth of the epidermis. Moderate lymphocytic infiltration in the upper dermis also was observed (Figure, A). The histologic findings of the plaque showed acanthosis, several pseudohorn cysts, hyperpigmentation of the basal layer, and a horizontal demarcation of the dermoepidermal junction (Figure, B).

Seborrheic keratosis is the most common benign epidermal tumor of the skin with variable appearance.¹ It usually begins with well-circumscribed, dull, flat, tan or brown patches that then grow into waxy verrucous papules.¹ There are many clinicopathologic variants of SK such as common SK, stucco keratosis, and dermatosis papulosa nigra in clinical variation, as well as acanthotic, hyperkeratotic, clonal, reticulated, irritated, and melanoacanthoma subtypes based on histological variation.^2,3

Seborrheic keratosis is a tumor of keratinocytic origin. Although genetics, sun exposure,⁴ and human papillomavirus infection⁵ are thought to be causative factors, the precise etiology of SK is unknown.¹

The histology of SK shows monotonous basaloid tumor cells without atypia. It generally is comprised of focal acanthosis and papillomatosis with a sharp flat base. Intraepithelial horn pseudocysts are notable features of SK and increased melanin often is seen.^2,6

Irritated SK is a histologic variant of SK that has been mechanically or chemically irritated or is involved in immunologic responses. Histologically, the dermis underlying an SK lesion filled with a dense lymphocytic infiltration is characteristic.^1,2

For symptomatic or cosmetically undesirable lesions, complete removal of the lesion is the preferred treatment. Cryotherapy, electrodesiccation followed by curettage, curettage followed by desiccation, laser ablation, and surgical excision are effective treatments.¹

The Diagnosis: Irritated Seborrheic Keratosis

Biopsies of one of the protruding papules and the underlying plaque were performed. The specimen from the papule showed hyperkeratosis, acanthosis, papillomatosis, and a flattened dermoepidermal junction with demarcated horizontal margin, which demonstrated apparent upward growth of the epidermis. Moderate lymphocytic infiltration in the upper dermis also was observed (Figure, A). The histologic findings of the plaque showed acanthosis, several pseudohorn cysts, hyperpigmentation of the basal layer, and a horizontal demarcation of the dermoepidermal junction (Figure, B).

Seborrheic keratosis is the most common benign epidermal tumor of the skin with variable appearance.¹ It usually begins with well-circumscribed, dull, flat, tan or brown patches that then grow into waxy verrucous papules.¹ There are many clinicopathologic variants of SK such as common SK, stucco keratosis, and dermatosis papulosa nigra in clinical variation, as well as acanthotic, hyperkeratotic, clonal, reticulated, irritated, and melanoacanthoma subtypes based on histological variation.^2,3

Seborrheic keratosis is a tumor of keratinocytic origin. Although genetics, sun exposure,⁴ and human papillomavirus infection⁵ are thought to be causative factors, the precise etiology of SK is unknown.¹

The histology of SK shows monotonous basaloid tumor cells without atypia. It generally is comprised of focal acanthosis and papillomatosis with a sharp flat base. Intraepithelial horn pseudocysts are notable features of SK and increased melanin often is seen.^2,6

Irritated SK is a histologic variant of SK that has been mechanically or chemically irritated or is involved in immunologic responses. Histologically, the dermis underlying an SK lesion filled with a dense lymphocytic infiltration is characteristic.^1,2

For symptomatic or cosmetically undesirable lesions, complete removal of the lesion is the preferred treatment. Cryotherapy, electrodesiccation followed by curettage, curettage followed by desiccation, laser ablation, and surgical excision are effective treatments.¹

The Diagnosis: Irritated Seborrheic Keratosis

Biopsies of one of the protruding papules and the underlying plaque were performed. The specimen from the papule showed hyperkeratosis, acanthosis, papillomatosis, and a flattened dermoepidermal junction with demarcated horizontal margin, which demonstrated apparent upward growth of the epidermis. Moderate lymphocytic infiltration in the upper dermis also was observed (Figure, A). The histologic findings of the plaque showed acanthosis, several pseudohorn cysts, hyperpigmentation of the basal layer, and a horizontal demarcation of the dermoepidermal junction (Figure, B).

Seborrheic keratosis is the most common benign epidermal tumor of the skin with variable appearance.¹ It usually begins with well-circumscribed, dull, flat, tan or brown patches that then grow into waxy verrucous papules.¹ There are many clinicopathologic variants of SK such as common SK, stucco keratosis, and dermatosis papulosa nigra in clinical variation, as well as acanthotic, hyperkeratotic, clonal, reticulated, irritated, and melanoacanthoma subtypes based on histological variation.^2,3

Seborrheic keratosis is a tumor of keratinocytic origin. Although genetics, sun exposure,⁴ and human papillomavirus infection⁵ are thought to be causative factors, the precise etiology of SK is unknown.¹

The histology of SK shows monotonous basaloid tumor cells without atypia. It generally is comprised of focal acanthosis and papillomatosis with a sharp flat base. Intraepithelial horn pseudocysts are notable features of SK and increased melanin often is seen.^2,6

Irritated SK is a histologic variant of SK that has been mechanically or chemically irritated or is involved in immunologic responses. Histologically, the dermis underlying an SK lesion filled with a dense lymphocytic infiltration is characteristic.^1,2

For symptomatic or cosmetically undesirable lesions, complete removal of the lesion is the preferred treatment. Cryotherapy, electrodesiccation followed by curettage, curettage followed by desiccation, laser ablation, and surgical excision are effective treatments.¹

Linear Basal Cell Carcinoma

On examination, the lesion was suspected to be a nevocellular nevus, foreign body granuloma, or venous lake; however, a skin biopsy specimen from the lesion on the left wrist revealed a tumor mass of basaloid cells, peripheral palisading arrangement, and scattered pigment granules (Figure 1). Tumor cells were negative for S-100 protein staining. These findings were consistent with a diagnosis of linear basal cell carcinoma (BCC). The lesion was removed by simple excision with primary closure of the wound. The surgical margins were free of tumor cells. The lesion had not recurred at 6-month follow-up. The patient was subsequently lost to follow-up.

Basal cell carcinoma presents with diverse clinical features, and several morphologic and histologic variants have been reported.¹ Linear BCC was described as a distinct clinical entity in 1985 by Lewis² in a 73-year-old man with a 20-mm linear pigmented lesion on the left cheek. Linear BCC often is not recognized or categorized as such by clinicians, as some may think that linear BCC is not a distinct entity but rather is one of the diverse clinical features of BCC.³ Linear BCC is believed to have specific clinical and histologic features and can be regarded as a distinct entity.⁴ Mavrikakis et al⁵ objectively defined linear BCC as a lesion that appeared to extend preferentially in one direction, resulting in a lesion with relatively straight borders and a length much greater than the width (3:1 ratio). Our patient presented with a linearly curved lesion, which is a rare feature of BCC.

Linear BCC occurs in equal proportions in men and women aged 40 to 87 years. More than 92% of reported patients were older than 60 years.⁶ The most common site for linear BCC is the periocular area, with the majority of lesions occurring on the cheek or lower eyelid. The second most common site is the neck, followed by the trunk, lower face, and inguinal skin fold.^3,5

The mechanism of linearity has been speculated. The majority of the reported cases of linear BCC have no history of trauma.⁷ However, focal trauma has been assumed to be a risk factor for the development of linear BCC, so the possibility that the Köbner phenomenon may be related to its linear pattern has been proposed.⁸ The Köbner phenomenon can be implicated in our case, as there was a history of surgery, which resulted in a scar.

Menzies⁹ described dermoscopic features of pigmented BCC and stated that the diagnosis of pigmented BCC required the presence of 1 or more of the following 6 positive features: large blue-gray ovoid nests; multiple blue-gray globules; maple leaf–like areas; spoke wheel areas; ulceration; and arborizing treelike vessels. In our case, there were multiple blue-gray globules and a streak that resembled ginseng (Figure 2).

Linear BCC is an uncommon morphological variant that requires clinical recognition. Our case was unique because of the ginsenglike streak on dermoscopy and possible association with a prior trauma.

Linear Basal Cell Carcinoma

On examination, the lesion was suspected to be a nevocellular nevus, foreign body granuloma, or venous lake; however, a skin biopsy specimen from the lesion on the left wrist revealed a tumor mass of basaloid cells, peripheral palisading arrangement, and scattered pigment granules (Figure 1). Tumor cells were negative for S-100 protein staining. These findings were consistent with a diagnosis of linear basal cell carcinoma (BCC). The lesion was removed by simple excision with primary closure of the wound. The surgical margins were free of tumor cells. The lesion had not recurred at 6-month follow-up. The patient was subsequently lost to follow-up.

Basal cell carcinoma presents with diverse clinical features, and several morphologic and histologic variants have been reported.¹ Linear BCC was described as a distinct clinical entity in 1985 by Lewis² in a 73-year-old man with a 20-mm linear pigmented lesion on the left cheek. Linear BCC often is not recognized or categorized as such by clinicians, as some may think that linear BCC is not a distinct entity but rather is one of the diverse clinical features of BCC.³ Linear BCC is believed to have specific clinical and histologic features and can be regarded as a distinct entity.⁴ Mavrikakis et al⁵ objectively defined linear BCC as a lesion that appeared to extend preferentially in one direction, resulting in a lesion with relatively straight borders and a length much greater than the width (3:1 ratio). Our patient presented with a linearly curved lesion, which is a rare feature of BCC.

Linear BCC occurs in equal proportions in men and women aged 40 to 87 years. More than 92% of reported patients were older than 60 years.⁶ The most common site for linear BCC is the periocular area, with the majority of lesions occurring on the cheek or lower eyelid. The second most common site is the neck, followed by the trunk, lower face, and inguinal skin fold.^3,5

The mechanism of linearity has been speculated. The majority of the reported cases of linear BCC have no history of trauma.⁷ However, focal trauma has been assumed to be a risk factor for the development of linear BCC, so the possibility that the Köbner phenomenon may be related to its linear pattern has been proposed.⁸ The Köbner phenomenon can be implicated in our case, as there was a history of surgery, which resulted in a scar.

Menzies⁹ described dermoscopic features of pigmented BCC and stated that the diagnosis of pigmented BCC required the presence of 1 or more of the following 6 positive features: large blue-gray ovoid nests; multiple blue-gray globules; maple leaf–like areas; spoke wheel areas; ulceration; and arborizing treelike vessels. In our case, there were multiple blue-gray globules and a streak that resembled ginseng (Figure 2).

Linear BCC is an uncommon morphological variant that requires clinical recognition. Our case was unique because of the ginsenglike streak on dermoscopy and possible association with a prior trauma.

Linear Basal Cell Carcinoma

On examination, the lesion was suspected to be a nevocellular nevus, foreign body granuloma, or venous lake; however, a skin biopsy specimen from the lesion on the left wrist revealed a tumor mass of basaloid cells, peripheral palisading arrangement, and scattered pigment granules (Figure 1). Tumor cells were negative for S-100 protein staining. These findings were consistent with a diagnosis of linear basal cell carcinoma (BCC). The lesion was removed by simple excision with primary closure of the wound. The surgical margins were free of tumor cells. The lesion had not recurred at 6-month follow-up. The patient was subsequently lost to follow-up.

Basal cell carcinoma presents with diverse clinical features, and several morphologic and histologic variants have been reported.¹ Linear BCC was described as a distinct clinical entity in 1985 by Lewis² in a 73-year-old man with a 20-mm linear pigmented lesion on the left cheek. Linear BCC often is not recognized or categorized as such by clinicians, as some may think that linear BCC is not a distinct entity but rather is one of the diverse clinical features of BCC.³ Linear BCC is believed to have specific clinical and histologic features and can be regarded as a distinct entity.⁴ Mavrikakis et al⁵ objectively defined linear BCC as a lesion that appeared to extend preferentially in one direction, resulting in a lesion with relatively straight borders and a length much greater than the width (3:1 ratio). Our patient presented with a linearly curved lesion, which is a rare feature of BCC.

Linear BCC occurs in equal proportions in men and women aged 40 to 87 years. More than 92% of reported patients were older than 60 years.⁶ The most common site for linear BCC is the periocular area, with the majority of lesions occurring on the cheek or lower eyelid. The second most common site is the neck, followed by the trunk, lower face, and inguinal skin fold.^3,5

The mechanism of linearity has been speculated. The majority of the reported cases of linear BCC have no history of trauma.⁷ However, focal trauma has been assumed to be a risk factor for the development of linear BCC, so the possibility that the Köbner phenomenon may be related to its linear pattern has been proposed.⁸ The Köbner phenomenon can be implicated in our case, as there was a history of surgery, which resulted in a scar.

Menzies⁹ described dermoscopic features of pigmented BCC and stated that the diagnosis of pigmented BCC required the presence of 1 or more of the following 6 positive features: large blue-gray ovoid nests; multiple blue-gray globules; maple leaf–like areas; spoke wheel areas; ulceration; and arborizing treelike vessels. In our case, there were multiple blue-gray globules and a streak that resembled ginseng (Figure 2).

Linear BCC is an uncommon morphological variant that requires clinical recognition. Our case was unique because of the ginsenglike streak on dermoscopy and possible association with a prior trauma.

The Diagnosis: Primary Cutaneous Mucinous Carcinoma

Primary cutaneous mucinous carcinoma is a rare tumor of the sweat glands that was first reported in 1952 by Lennox et al.¹ These tumors are slow growing and have a predilection for the head and neck, with the eyelid being the most commonly reported location.² In general, they present as erythematous asymptomatic nodules measuring less than 7 cm in diameter.^2-4 Primary cutaneous mucinous carcinoma tends to have a good prognosis with complete resection, but cases of metastasis and recurrence have been reported.² Although there is no standard of care, treatment typically consists of surgical management, as the tumors are nonresponsive to chemotherapy or radiation.⁴ Kamalpour et al² compared outcomes for Mohs micrographic surgery versus standard excision, the former showing a lower percentage of poor outcomes. Of note, there were fewer cases treated with Mohs surgery in this study; only more recently reported cases have been treated with Mohs surgery.

Histologically, primary cutaneous mucinous carcinoma is composed of cords, tubules, and lobules of epithelial cells floating in large pools of basophilic mucin, separated by thin fibrovascular septa.⁵ It can be difficult to distinguish a primary tumor from a mucinous carcinoma metastasis with histology alone, especially on the breasts and in the gastrointestinal tract. Immunohistochemistry can be helpful in determining the origin of the tumor. A homologue of p53, p63 expressed in basal and myoepithelial cells of the skin can aid in the confirmation of a primary tumor when present.^6,7 Negative staining for cytokeratin 20 and positive staining for cytokeratin 7 also are helpful in distinguishing a primary cutaneous mucinous carcinoma from a gastrointestinal tract metastasis.^4,8

In our patient, no other symptoms were present that raised concern for an internal malignancy. Findings that supported a primary versus metastatic tumor included the clinicopathologic findings (Figure) as well as positive p63, cytokeratin 7, and negative cytokeratin 20 staining. The initial standard excision had tumor cells within 1 mm of the specimen margin; thus, a subsequent wider reexcision was performed. Reexcision was negative for tumor cells. Close follow-up with a primary care physician was recommended, with emphasis on colon and breast cancer screening. A follow-up mammogram was negative for breast cancer.

The Diagnosis: Primary Cutaneous Mucinous Carcinoma

Primary cutaneous mucinous carcinoma is a rare tumor of the sweat glands that was first reported in 1952 by Lennox et al.¹ These tumors are slow growing and have a predilection for the head and neck, with the eyelid being the most commonly reported location.² In general, they present as erythematous asymptomatic nodules measuring less than 7 cm in diameter.^2-4 Primary cutaneous mucinous carcinoma tends to have a good prognosis with complete resection, but cases of metastasis and recurrence have been reported.² Although there is no standard of care, treatment typically consists of surgical management, as the tumors are nonresponsive to chemotherapy or radiation.⁴ Kamalpour et al² compared outcomes for Mohs micrographic surgery versus standard excision, the former showing a lower percentage of poor outcomes. Of note, there were fewer cases treated with Mohs surgery in this study; only more recently reported cases have been treated with Mohs surgery.

Histologically, primary cutaneous mucinous carcinoma is composed of cords, tubules, and lobules of epithelial cells floating in large pools of basophilic mucin, separated by thin fibrovascular septa.⁵ It can be difficult to distinguish a primary tumor from a mucinous carcinoma metastasis with histology alone, especially on the breasts and in the gastrointestinal tract. Immunohistochemistry can be helpful in determining the origin of the tumor. A homologue of p53, p63 expressed in basal and myoepithelial cells of the skin can aid in the confirmation of a primary tumor when present.^6,7 Negative staining for cytokeratin 20 and positive staining for cytokeratin 7 also are helpful in distinguishing a primary cutaneous mucinous carcinoma from a gastrointestinal tract metastasis.^4,8

In our patient, no other symptoms were present that raised concern for an internal malignancy. Findings that supported a primary versus metastatic tumor included the clinicopathologic findings (Figure) as well as positive p63, cytokeratin 7, and negative cytokeratin 20 staining. The initial standard excision had tumor cells within 1 mm of the specimen margin; thus, a subsequent wider reexcision was performed. Reexcision was negative for tumor cells. Close follow-up with a primary care physician was recommended, with emphasis on colon and breast cancer screening. A follow-up mammogram was negative for breast cancer.

The Diagnosis: Primary Cutaneous Mucinous Carcinoma

Primary cutaneous mucinous carcinoma is a rare tumor of the sweat glands that was first reported in 1952 by Lennox et al.¹ These tumors are slow growing and have a predilection for the head and neck, with the eyelid being the most commonly reported location.² In general, they present as erythematous asymptomatic nodules measuring less than 7 cm in diameter.^2-4 Primary cutaneous mucinous carcinoma tends to have a good prognosis with complete resection, but cases of metastasis and recurrence have been reported.² Although there is no standard of care, treatment typically consists of surgical management, as the tumors are nonresponsive to chemotherapy or radiation.⁴ Kamalpour et al² compared outcomes for Mohs micrographic surgery versus standard excision, the former showing a lower percentage of poor outcomes. Of note, there were fewer cases treated with Mohs surgery in this study; only more recently reported cases have been treated with Mohs surgery.

Histologically, primary cutaneous mucinous carcinoma is composed of cords, tubules, and lobules of epithelial cells floating in large pools of basophilic mucin, separated by thin fibrovascular septa.⁵ It can be difficult to distinguish a primary tumor from a mucinous carcinoma metastasis with histology alone, especially on the breasts and in the gastrointestinal tract. Immunohistochemistry can be helpful in determining the origin of the tumor. A homologue of p53, p63 expressed in basal and myoepithelial cells of the skin can aid in the confirmation of a primary tumor when present.^6,7 Negative staining for cytokeratin 20 and positive staining for cytokeratin 7 also are helpful in distinguishing a primary cutaneous mucinous carcinoma from a gastrointestinal tract metastasis.^4,8

In our patient, no other symptoms were present that raised concern for an internal malignancy. Findings that supported a primary versus metastatic tumor included the clinicopathologic findings (Figure) as well as positive p63, cytokeratin 7, and negative cytokeratin 20 staining. The initial standard excision had tumor cells within 1 mm of the specimen margin; thus, a subsequent wider reexcision was performed. Reexcision was negative for tumor cells. Close follow-up with a primary care physician was recommended, with emphasis on colon and breast cancer screening. A follow-up mammogram was negative for breast cancer.

The Diagnosis: Eccrine Angiomatous Hamartoma

Given the progression of symptoms 3 months prior to presentation, an excisional biopsy was performed (Figure 1). Hematoxylin and eosin staining showed prominent eccrine sweat glands and vessels surrounded by superficially located adipose tissue in the mid and deep dermis (Figure 2).

Eccrine angiomatous hamartoma (EAH) is an uncommon benign tumor typically located on the arms and legs or trunk. It is usually solitary, though cases with multiple lesions have been reported.^1,2 Most cases are diagnosed in childhood as either congenital or acquired lesions. However, EAHs can develop in adulthood and have been described in patients up to 70 years of age.³ The median age of diagnosis is 10 years,² indicating that EAH is primarily a pediatric tumor. There is no gender predilection.

Approximately 35% to 66% of patients report pain, pruritus, or hyperhidrosis associated with EAHs, though this incidence may be overrepresented because patients tend to present when the lesions become symptomatic.^2-5 The pain is attributed to nerve fibers infiltrating the tumor. Hypertrichosis also has been described and is thought to be due to hair follicles within the hamartoma.

Histologically, EAHs are characterized by normal-appearing eccrine glands mingled with venules and capillaries. Additional variable pathologic findings include lipomatous, pilar, lymphatic, or mucinous features.² Other vascular anomalies such as hemangiomas or arteriovenous malformations occasionally have been described in association with EAH. The vessels stain for ulex europaeus 1 and factor VIII. Eccrine glands stain for S-100 protein, carcinoembryonic antigen, epithelial membrane antigen, and cytokeratin CAM 5.2. In light of a publication proposing that EAH is a lymphatic proliferation,⁶ a D2-40 stain was performed on the specimen and was negative. 

Eccrine angiomatous hamartoma has been reported to grow mainly during childhood, puberty, or pregnancy, presumably due to hormonal influences.⁷ There are few reports of EAH enlarging in middle-aged adults, and even fewer without pain during the growth phase. It is unclear what triggered the growth in our otherwise healthy postmenopausal patient.

Eccrine angiomatous hamartoma does not have malignant potential and thus treatment is optional and based on relief of symptoms. Simple excision of the EAH usually is curative, but recurrences can occur.⁴ Botulinum toxin also has been used to treat hyperhidrosis in tumors that are too large for resection. Treatment with lasers such as the pulsed dye laser and Nd:YAG laser has not been successful.⁸ A case of spontaneous regression has been reported.¹

Liposuction was considered in our patient given the substantial adipose tissue on biopsy. The patient ultimately declined treatment. This case highlights that EAH can present in adulthood and should be considered in the differential diagnosis of an enlarging but otherwise asymptomatic vascular tumor.

The Diagnosis: Eccrine Angiomatous Hamartoma

Given the progression of symptoms 3 months prior to presentation, an excisional biopsy was performed (Figure 1). Hematoxylin and eosin staining showed prominent eccrine sweat glands and vessels surrounded by superficially located adipose tissue in the mid and deep dermis (Figure 2).

Eccrine angiomatous hamartoma (EAH) is an uncommon benign tumor typically located on the arms and legs or trunk. It is usually solitary, though cases with multiple lesions have been reported.^1,2 Most cases are diagnosed in childhood as either congenital or acquired lesions. However, EAHs can develop in adulthood and have been described in patients up to 70 years of age.³ The median age of diagnosis is 10 years,² indicating that EAH is primarily a pediatric tumor. There is no gender predilection.

Approximately 35% to 66% of patients report pain, pruritus, or hyperhidrosis associated with EAHs, though this incidence may be overrepresented because patients tend to present when the lesions become symptomatic.^2-5 The pain is attributed to nerve fibers infiltrating the tumor. Hypertrichosis also has been described and is thought to be due to hair follicles within the hamartoma.

Histologically, EAHs are characterized by normal-appearing eccrine glands mingled with venules and capillaries. Additional variable pathologic findings include lipomatous, pilar, lymphatic, or mucinous features.² Other vascular anomalies such as hemangiomas or arteriovenous malformations occasionally have been described in association with EAH. The vessels stain for ulex europaeus 1 and factor VIII. Eccrine glands stain for S-100 protein, carcinoembryonic antigen, epithelial membrane antigen, and cytokeratin CAM 5.2. In light of a publication proposing that EAH is a lymphatic proliferation,⁶ a D2-40 stain was performed on the specimen and was negative. 

Eccrine angiomatous hamartoma has been reported to grow mainly during childhood, puberty, or pregnancy, presumably due to hormonal influences.⁷ There are few reports of EAH enlarging in middle-aged adults, and even fewer without pain during the growth phase. It is unclear what triggered the growth in our otherwise healthy postmenopausal patient.

Eccrine angiomatous hamartoma does not have malignant potential and thus treatment is optional and based on relief of symptoms. Simple excision of the EAH usually is curative, but recurrences can occur.⁴ Botulinum toxin also has been used to treat hyperhidrosis in tumors that are too large for resection. Treatment with lasers such as the pulsed dye laser and Nd:YAG laser has not been successful.⁸ A case of spontaneous regression has been reported.¹

Liposuction was considered in our patient given the substantial adipose tissue on biopsy. The patient ultimately declined treatment. This case highlights that EAH can present in adulthood and should be considered in the differential diagnosis of an enlarging but otherwise asymptomatic vascular tumor.

The Diagnosis: Eccrine Angiomatous Hamartoma

Given the progression of symptoms 3 months prior to presentation, an excisional biopsy was performed (Figure 1). Hematoxylin and eosin staining showed prominent eccrine sweat glands and vessels surrounded by superficially located adipose tissue in the mid and deep dermis (Figure 2).

Eccrine angiomatous hamartoma (EAH) is an uncommon benign tumor typically located on the arms and legs or trunk. It is usually solitary, though cases with multiple lesions have been reported.^1,2 Most cases are diagnosed in childhood as either congenital or acquired lesions. However, EAHs can develop in adulthood and have been described in patients up to 70 years of age.³ The median age of diagnosis is 10 years,² indicating that EAH is primarily a pediatric tumor. There is no gender predilection.

Approximately 35% to 66% of patients report pain, pruritus, or hyperhidrosis associated with EAHs, though this incidence may be overrepresented because patients tend to present when the lesions become symptomatic.^2-5 The pain is attributed to nerve fibers infiltrating the tumor. Hypertrichosis also has been described and is thought to be due to hair follicles within the hamartoma.

Histologically, EAHs are characterized by normal-appearing eccrine glands mingled with venules and capillaries. Additional variable pathologic findings include lipomatous, pilar, lymphatic, or mucinous features.² Other vascular anomalies such as hemangiomas or arteriovenous malformations occasionally have been described in association with EAH. The vessels stain for ulex europaeus 1 and factor VIII. Eccrine glands stain for S-100 protein, carcinoembryonic antigen, epithelial membrane antigen, and cytokeratin CAM 5.2. In light of a publication proposing that EAH is a lymphatic proliferation,⁶ a D2-40 stain was performed on the specimen and was negative. 

Eccrine angiomatous hamartoma has been reported to grow mainly during childhood, puberty, or pregnancy, presumably due to hormonal influences.⁷ There are few reports of EAH enlarging in middle-aged adults, and even fewer without pain during the growth phase. It is unclear what triggered the growth in our otherwise healthy postmenopausal patient.

Eccrine angiomatous hamartoma does not have malignant potential and thus treatment is optional and based on relief of symptoms. Simple excision of the EAH usually is curative, but recurrences can occur.⁴ Botulinum toxin also has been used to treat hyperhidrosis in tumors that are too large for resection. Treatment with lasers such as the pulsed dye laser and Nd:YAG laser has not been successful.⁸ A case of spontaneous regression has been reported.¹

Liposuction was considered in our patient given the substantial adipose tissue on biopsy. The patient ultimately declined treatment. This case highlights that EAH can present in adulthood and should be considered in the differential diagnosis of an enlarging but otherwise asymptomatic vascular tumor.