Cutis

In the late 19th century, Brooke and Spiegler described the familial occurrence of multiple tumors of the skin appendages. Synonyms have included familial cylindromatosis, turban tumor syndrome, and Brooke-Spiegler syndrome (BSS).1 In this report, we describe a patient with pegged teeth and BSS. We discuss the pathogenesis, diagnosis, genetic testing, and treatment options for this interesting syndrome.

Case Report
A 40-year-old white woman presented in 1997 for evaluation of numerous flesh-colored papules on her face. One of the lesions was biopsied in 1999 and diagnosed as a trichoepithelioma (Figure 1). These particular lesions had been present since she was 13 years of age, increasing in size and number with time. Subsequently, in December 2003, she presented with a 0.8-cm pink papule in the left preauricular area; a biopsy was performed and a spiradenoma in association with a trichoepithelioma was diagnosed. In January 2006, she presented with enlarging "bumps" on her scalp. She denied any substantial pain, pruritus, or other symptoms, but was rather concerned about the recent growth of lesions, both in size and number. Her medical history was noncontributory. However, there was a family history of similar lesions on the face and scalp of a great-aunt and uncle. No workup or genetic testing was ever performed.

Physical examination revealed a healthy, well-nourished, middle-aged woman. There were numerous symmetrically distributed flesh-colored to off-white firm papules involving the bilateral nasolabial folds, coalescing in areas to form plaques (Figure 2). There were 3 pink, firm, smooth, well-circumscribed nodules with overlying telangiectases involving the vertex and crown of the scalp, measuring 0.7X0.7 cm, 1.4X1.1 cm, and 1.4X1.4 cm in size. There was mild tenderness to palpation of all 3 lesions. Most interestingly, examination of the oral cavity revealed pegged (conical) teeth (Figure 3). It was not clear if they were primary or secondary teeth. There was no history of incontinentia pigmenti or any other ectodermal dysplasia in the patient or family members. Further evaluation of the hair and nails revealed no additional abnormalities.

The differential diagnoses for the scalp lesions included pilar cysts, basal or squamous cell carcinomas, spiradenomas, cylindromas, trichoblastomas, neurofibromas, and keloids or hypertrophic scars. The patient underwent an excisional biopsy of the smallest lesion in February 2006. Subsequently, excisional biopsies were performed on the other 2 lesions in April and July 2006. The first specimen revealed variably sized discrete aggregations of cuboidal epithelial cells with a rim of thickened eosinophilic basement membrane material surrounding tumor islands. There were 2 types of epithelial cells: cells with small, dark-staining nuclei present at the periphery in a palisading fashion, and light-staining nuclei lying in the center of the aggregations. Sweat duct lumina were appreciated within the tumor islands, and a diagnosis of cylindroma was made. The second biopsy showed a single, large, well-demarcated nodule of cuboidal epithelial cells arranged in interweaving cords present in the dermis. Again, there were 2 types of epithelial cells: smaller cells with dark nuclei lying at the periphery of the cords, and cells with larger pale nuclei in the center of the cords, associated with lumina. A diagnosis of spiradenoma was rendered. Based on the clinical findings and histopathologic diagnoses of trichoepithelioma, cylindroma, and spiradenoma, the patient received a diagnosis of BSS. Treatment for the trichoepitheliomas consisted of several glycolic acid peels, and the patient was pleased with the results. Furthermore, complete excisional biopsies were performed for all tumors on the scalp. The patient considered genetic testing for herself and family members.

Comment
Brooke-Spiegler syndrome is inherited in an autosomal dominant fashion with complete penetrance and variable expression. Both interfamilial and intrafamilial phenotypic variability have been well-documented in BSS; thus, a correlation between genotype and phenotype is lacking.2 Brooke-Spiegler syndrome is uncommon, with a female to male ratio of 2 to 1.1 Characteristically, patients present with the classic triad of cylindromas, trichoepitheliomas, and spiradenomas. Often, other adnexal tumors are observed, including but not limited to trichoblastomas, basal cell carcinomas, milia, organoid nevi, and syringomas.3 It was initially believed that cylindromas and spiradenomas showed sweat gland differentiation and trichoepitheliomas showed follicular differentiation.4 This combination represents an unusual inherited tumor diathesis involving neoplasms derived from pluripotential basal cells with adnexal differentiation along both sweat gland and follicular lineages.5-7 Typically, these tumors are located in the head and neck region, appear in puberty to early adulthood, and gradually increase in size and number throughout life.8 Malignant transformation of cylindromas in particular is quite rare, but metastasis in the event of malignancy is not infrequent.9-11 Malignancy is more frequent in patients with BSS rather than solitary cylindroma.10-12 Patients also are at risk for developing benign and malignant tumors of the salivary glands, particularly the parotid, including adenocarcinoma.4,6,8,13 In affected families, mutations have been demonstrated in the cylindromatosis gene, CYLD, located on band 16q12-13.¹⁴ This gene consists of 20 exons and reveals the characteristic attributes of a tumor suppressor gene with loss of heterozygosity.1,15,16 CYLD plays a role in governing cell cycle and apoptosis.9 Mutational changes in the CYLD gene could affect the normal regulation of the stem cell population of the folliculosebaceousapocrine unit. In turn, mutations in the genes that regulate proliferation and differentiation of the putative stem cells, possibly located in the bulge region of the hair follicle,3 could give rise to different combinations of adnexal skin tumors.1,2,17-19 More recently, spiradenomas have been proposed to be apocrine tumors on the basis of adnexal morphogenesis and their close association with follicular and apocrine tumors in BSS.10 The morphogenesis of both apocrine and sebaceous glands is dependent on the hair follicle because the glands develop from epithelial buds arising directly above the isthmus. However, eccrine glands develop from the base of the interfollicular rete ridges of embryonic skin. Cylindromas and spiradenomas are not eccrine tumors but neoplasms of the folliculosebaceousapocrine unit, as demonstrated by the occurrence of sebaceous and trichoblastic differentiation in spiradenocylindromas. It is hypothesized that cylindromas and spiradenomas may be polar extremes of a spectrum of adnexal neoplasms with apocrine differentiation.13 Since the initial observation of mutations in the CYLD1 gene as cause for BSS,15 a host of different mutations have been reported, including frameshift mutations,1,20 splice site mutations,1 small deletions and insertions,1,15,21 and novel missense mutations.8 Most mutations lead to a premature translational stop, which disrupts the protein function.21 The CYLD gene interacts with several members of the nuclear factor-κΒ signaling pathway, which play important roles in inflammation, immune response, and oncogenesis. Inhibition of the CYLD gene enhances activation of the transcription factor nuclear factor-κΒ and leads to increased resistance to apoptosis and advanced carcinogenesis,21 which also results in compromise of the early steps in the development of epidermal appendages, including hair follicles and sweat glands.22 The exact mechanisms of CYLD-dependent tumorigenesis in the skin remain to be established. Cylindromas located on the head and neck region may eventually cover the entire scalp, resulting in so-called turban tumors.8 Mutational screening for the CYLD gene is beneficial to patients with multiple cylindromas and/or trichoepitheliomas as well as their family members. Physicians caring for patients and family members affected with BSS should contact the medical genetics department of their respective local medical school or academic medical center. Early identification of mutation carriers and appropriate genetic counseling may improve the therapeutic management to avoid complications such as disfigurement (turban tumor) or malignant transformation.21 Excision of all cylindromas and spiradenomas is recommended due to the low risk for malignant potential (cylindrocarcinoma and spiradenocarcinoma).8 If untreated, BSS can cause considerable disfigurement and discomfort, and severely neglected cases may require scalp surgery and reconstruction.23 Additionally, laser treatments, such as CO2 and erbium:YAG lasers, have been used for surgical destruction of several of the adnexal tumors (cylindromas and trichoepitheliomas), though the former ideally should be excised for histology because of the low risk for malignant transformation.5,9 Dermabrasion, chemical peels, electrodesiccation, and cryotherapy also may be considered as alternative treatment modalities.9 Brummelkamp et al24 demonstrated that inhibitory effects caused by CYLD gene mutations potentially can be reversed by application of salicylates or prostaglandin A. This discovery may give hope for novel therapeutic approaches in the future. The presence of pegged (conical) teeth in our patient is unusual, as this finding has not been described in BSS. The question remains, are these truly pegged teeth, and if so, is it merely an incidental (idiopathic) finding or rather part of an altogether new syndrome? As a result, genetic testing is extremely inviting.

Conclusion
Brooke-Spiegler syndrome consists of the classic triad of cylindromas, trichoepitheliomas, and spiradenomas. Mutations occur in the CYLD gene on band 16q12-13. Brooke-Spiegler syndrome is theorized as reflecting genetic dysfunction in the regulation of the folliculosebaceousapocrine unit. Early diagnosis is important with confirmatory genetic testing of the patient and family members. Further studies including genetic testing will need to be conducted to determine the relationship between pegged (conical) teeth and BSS.

In the late 19th century, Brooke and Spiegler described the familial occurrence of multiple tumors of the skin appendages. Synonyms have included familial cylindromatosis, turban tumor syndrome, and Brooke-Spiegler syndrome (BSS).1 In this report, we describe a patient with pegged teeth and BSS. We discuss the pathogenesis, diagnosis, genetic testing, and treatment options for this interesting syndrome.

Case Report
A 40-year-old white woman presented in 1997 for evaluation of numerous flesh-colored papules on her face. One of the lesions was biopsied in 1999 and diagnosed as a trichoepithelioma (Figure 1). These particular lesions had been present since she was 13 years of age, increasing in size and number with time. Subsequently, in December 2003, she presented with a 0.8-cm pink papule in the left preauricular area; a biopsy was performed and a spiradenoma in association with a trichoepithelioma was diagnosed. In January 2006, she presented with enlarging "bumps" on her scalp. She denied any substantial pain, pruritus, or other symptoms, but was rather concerned about the recent growth of lesions, both in size and number. Her medical history was noncontributory. However, there was a family history of similar lesions on the face and scalp of a great-aunt and uncle. No workup or genetic testing was ever performed.

Physical examination revealed a healthy, well-nourished, middle-aged woman. There were numerous symmetrically distributed flesh-colored to off-white firm papules involving the bilateral nasolabial folds, coalescing in areas to form plaques (Figure 2). There were 3 pink, firm, smooth, well-circumscribed nodules with overlying telangiectases involving the vertex and crown of the scalp, measuring 0.7X0.7 cm, 1.4X1.1 cm, and 1.4X1.4 cm in size. There was mild tenderness to palpation of all 3 lesions. Most interestingly, examination of the oral cavity revealed pegged (conical) teeth (Figure 3). It was not clear if they were primary or secondary teeth. There was no history of incontinentia pigmenti or any other ectodermal dysplasia in the patient or family members. Further evaluation of the hair and nails revealed no additional abnormalities.

The differential diagnoses for the scalp lesions included pilar cysts, basal or squamous cell carcinomas, spiradenomas, cylindromas, trichoblastomas, neurofibromas, and keloids or hypertrophic scars. The patient underwent an excisional biopsy of the smallest lesion in February 2006. Subsequently, excisional biopsies were performed on the other 2 lesions in April and July 2006. The first specimen revealed variably sized discrete aggregations of cuboidal epithelial cells with a rim of thickened eosinophilic basement membrane material surrounding tumor islands. There were 2 types of epithelial cells: cells with small, dark-staining nuclei present at the periphery in a palisading fashion, and light-staining nuclei lying in the center of the aggregations. Sweat duct lumina were appreciated within the tumor islands, and a diagnosis of cylindroma was made. The second biopsy showed a single, large, well-demarcated nodule of cuboidal epithelial cells arranged in interweaving cords present in the dermis. Again, there were 2 types of epithelial cells: smaller cells with dark nuclei lying at the periphery of the cords, and cells with larger pale nuclei in the center of the cords, associated with lumina. A diagnosis of spiradenoma was rendered. Based on the clinical findings and histopathologic diagnoses of trichoepithelioma, cylindroma, and spiradenoma, the patient received a diagnosis of BSS. Treatment for the trichoepitheliomas consisted of several glycolic acid peels, and the patient was pleased with the results. Furthermore, complete excisional biopsies were performed for all tumors on the scalp. The patient considered genetic testing for herself and family members.

Comment
Brooke-Spiegler syndrome is inherited in an autosomal dominant fashion with complete penetrance and variable expression. Both interfamilial and intrafamilial phenotypic variability have been well-documented in BSS; thus, a correlation between genotype and phenotype is lacking.2 Brooke-Spiegler syndrome is uncommon, with a female to male ratio of 2 to 1.1 Characteristically, patients present with the classic triad of cylindromas, trichoepitheliomas, and spiradenomas. Often, other adnexal tumors are observed, including but not limited to trichoblastomas, basal cell carcinomas, milia, organoid nevi, and syringomas.3 It was initially believed that cylindromas and spiradenomas showed sweat gland differentiation and trichoepitheliomas showed follicular differentiation.4 This combination represents an unusual inherited tumor diathesis involving neoplasms derived from pluripotential basal cells with adnexal differentiation along both sweat gland and follicular lineages.5-7 Typically, these tumors are located in the head and neck region, appear in puberty to early adulthood, and gradually increase in size and number throughout life.8 Malignant transformation of cylindromas in particular is quite rare, but metastasis in the event of malignancy is not infrequent.9-11 Malignancy is more frequent in patients with BSS rather than solitary cylindroma.10-12 Patients also are at risk for developing benign and malignant tumors of the salivary glands, particularly the parotid, including adenocarcinoma.4,6,8,13 In affected families, mutations have been demonstrated in the cylindromatosis gene, CYLD, located on band 16q12-13.¹⁴ This gene consists of 20 exons and reveals the characteristic attributes of a tumor suppressor gene with loss of heterozygosity.1,15,16 CYLD plays a role in governing cell cycle and apoptosis.9 Mutational changes in the CYLD gene could affect the normal regulation of the stem cell population of the folliculosebaceousapocrine unit. In turn, mutations in the genes that regulate proliferation and differentiation of the putative stem cells, possibly located in the bulge region of the hair follicle,3 could give rise to different combinations of adnexal skin tumors.1,2,17-19 More recently, spiradenomas have been proposed to be apocrine tumors on the basis of adnexal morphogenesis and their close association with follicular and apocrine tumors in BSS.10 The morphogenesis of both apocrine and sebaceous glands is dependent on the hair follicle because the glands develop from epithelial buds arising directly above the isthmus. However, eccrine glands develop from the base of the interfollicular rete ridges of embryonic skin. Cylindromas and spiradenomas are not eccrine tumors but neoplasms of the folliculosebaceousapocrine unit, as demonstrated by the occurrence of sebaceous and trichoblastic differentiation in spiradenocylindromas. It is hypothesized that cylindromas and spiradenomas may be polar extremes of a spectrum of adnexal neoplasms with apocrine differentiation.13 Since the initial observation of mutations in the CYLD1 gene as cause for BSS,15 a host of different mutations have been reported, including frameshift mutations,1,20 splice site mutations,1 small deletions and insertions,1,15,21 and novel missense mutations.8 Most mutations lead to a premature translational stop, which disrupts the protein function.21 The CYLD gene interacts with several members of the nuclear factor-κΒ signaling pathway, which play important roles in inflammation, immune response, and oncogenesis. Inhibition of the CYLD gene enhances activation of the transcription factor nuclear factor-κΒ and leads to increased resistance to apoptosis and advanced carcinogenesis,21 which also results in compromise of the early steps in the development of epidermal appendages, including hair follicles and sweat glands.22 The exact mechanisms of CYLD-dependent tumorigenesis in the skin remain to be established. Cylindromas located on the head and neck region may eventually cover the entire scalp, resulting in so-called turban tumors.8 Mutational screening for the CYLD gene is beneficial to patients with multiple cylindromas and/or trichoepitheliomas as well as their family members. Physicians caring for patients and family members affected with BSS should contact the medical genetics department of their respective local medical school or academic medical center. Early identification of mutation carriers and appropriate genetic counseling may improve the therapeutic management to avoid complications such as disfigurement (turban tumor) or malignant transformation.21 Excision of all cylindromas and spiradenomas is recommended due to the low risk for malignant potential (cylindrocarcinoma and spiradenocarcinoma).8 If untreated, BSS can cause considerable disfigurement and discomfort, and severely neglected cases may require scalp surgery and reconstruction.23 Additionally, laser treatments, such as CO2 and erbium:YAG lasers, have been used for surgical destruction of several of the adnexal tumors (cylindromas and trichoepitheliomas), though the former ideally should be excised for histology because of the low risk for malignant transformation.5,9 Dermabrasion, chemical peels, electrodesiccation, and cryotherapy also may be considered as alternative treatment modalities.9 Brummelkamp et al24 demonstrated that inhibitory effects caused by CYLD gene mutations potentially can be reversed by application of salicylates or prostaglandin A. This discovery may give hope for novel therapeutic approaches in the future. The presence of pegged (conical) teeth in our patient is unusual, as this finding has not been described in BSS. The question remains, are these truly pegged teeth, and if so, is it merely an incidental (idiopathic) finding or rather part of an altogether new syndrome? As a result, genetic testing is extremely inviting.

Conclusion
Brooke-Spiegler syndrome consists of the classic triad of cylindromas, trichoepitheliomas, and spiradenomas. Mutations occur in the CYLD gene on band 16q12-13. Brooke-Spiegler syndrome is theorized as reflecting genetic dysfunction in the regulation of the folliculosebaceousapocrine unit. Early diagnosis is important with confirmatory genetic testing of the patient and family members. Further studies including genetic testing will need to be conducted to determine the relationship between pegged (conical) teeth and BSS.

In the late 19th century, Brooke and Spiegler described the familial occurrence of multiple tumors of the skin appendages. Synonyms have included familial cylindromatosis, turban tumor syndrome, and Brooke-Spiegler syndrome (BSS).1 In this report, we describe a patient with pegged teeth and BSS. We discuss the pathogenesis, diagnosis, genetic testing, and treatment options for this interesting syndrome.

Case Report
A 40-year-old white woman presented in 1997 for evaluation of numerous flesh-colored papules on her face. One of the lesions was biopsied in 1999 and diagnosed as a trichoepithelioma (Figure 1). These particular lesions had been present since she was 13 years of age, increasing in size and number with time. Subsequently, in December 2003, she presented with a 0.8-cm pink papule in the left preauricular area; a biopsy was performed and a spiradenoma in association with a trichoepithelioma was diagnosed. In January 2006, she presented with enlarging "bumps" on her scalp. She denied any substantial pain, pruritus, or other symptoms, but was rather concerned about the recent growth of lesions, both in size and number. Her medical history was noncontributory. However, there was a family history of similar lesions on the face and scalp of a great-aunt and uncle. No workup or genetic testing was ever performed.

Physical examination revealed a healthy, well-nourished, middle-aged woman. There were numerous symmetrically distributed flesh-colored to off-white firm papules involving the bilateral nasolabial folds, coalescing in areas to form plaques (Figure 2). There were 3 pink, firm, smooth, well-circumscribed nodules with overlying telangiectases involving the vertex and crown of the scalp, measuring 0.7X0.7 cm, 1.4X1.1 cm, and 1.4X1.4 cm in size. There was mild tenderness to palpation of all 3 lesions. Most interestingly, examination of the oral cavity revealed pegged (conical) teeth (Figure 3). It was not clear if they were primary or secondary teeth. There was no history of incontinentia pigmenti or any other ectodermal dysplasia in the patient or family members. Further evaluation of the hair and nails revealed no additional abnormalities.

The differential diagnoses for the scalp lesions included pilar cysts, basal or squamous cell carcinomas, spiradenomas, cylindromas, trichoblastomas, neurofibromas, and keloids or hypertrophic scars. The patient underwent an excisional biopsy of the smallest lesion in February 2006. Subsequently, excisional biopsies were performed on the other 2 lesions in April and July 2006. The first specimen revealed variably sized discrete aggregations of cuboidal epithelial cells with a rim of thickened eosinophilic basement membrane material surrounding tumor islands. There were 2 types of epithelial cells: cells with small, dark-staining nuclei present at the periphery in a palisading fashion, and light-staining nuclei lying in the center of the aggregations. Sweat duct lumina were appreciated within the tumor islands, and a diagnosis of cylindroma was made. The second biopsy showed a single, large, well-demarcated nodule of cuboidal epithelial cells arranged in interweaving cords present in the dermis. Again, there were 2 types of epithelial cells: smaller cells with dark nuclei lying at the periphery of the cords, and cells with larger pale nuclei in the center of the cords, associated with lumina. A diagnosis of spiradenoma was rendered. Based on the clinical findings and histopathologic diagnoses of trichoepithelioma, cylindroma, and spiradenoma, the patient received a diagnosis of BSS. Treatment for the trichoepitheliomas consisted of several glycolic acid peels, and the patient was pleased with the results. Furthermore, complete excisional biopsies were performed for all tumors on the scalp. The patient considered genetic testing for herself and family members.

Comment
Brooke-Spiegler syndrome is inherited in an autosomal dominant fashion with complete penetrance and variable expression. Both interfamilial and intrafamilial phenotypic variability have been well-documented in BSS; thus, a correlation between genotype and phenotype is lacking.2 Brooke-Spiegler syndrome is uncommon, with a female to male ratio of 2 to 1.1 Characteristically, patients present with the classic triad of cylindromas, trichoepitheliomas, and spiradenomas. Often, other adnexal tumors are observed, including but not limited to trichoblastomas, basal cell carcinomas, milia, organoid nevi, and syringomas.3 It was initially believed that cylindromas and spiradenomas showed sweat gland differentiation and trichoepitheliomas showed follicular differentiation.4 This combination represents an unusual inherited tumor diathesis involving neoplasms derived from pluripotential basal cells with adnexal differentiation along both sweat gland and follicular lineages.5-7 Typically, these tumors are located in the head and neck region, appear in puberty to early adulthood, and gradually increase in size and number throughout life.8 Malignant transformation of cylindromas in particular is quite rare, but metastasis in the event of malignancy is not infrequent.9-11 Malignancy is more frequent in patients with BSS rather than solitary cylindroma.10-12 Patients also are at risk for developing benign and malignant tumors of the salivary glands, particularly the parotid, including adenocarcinoma.4,6,8,13 In affected families, mutations have been demonstrated in the cylindromatosis gene, CYLD, located on band 16q12-13.¹⁴ This gene consists of 20 exons and reveals the characteristic attributes of a tumor suppressor gene with loss of heterozygosity.1,15,16 CYLD plays a role in governing cell cycle and apoptosis.9 Mutational changes in the CYLD gene could affect the normal regulation of the stem cell population of the folliculosebaceousapocrine unit. In turn, mutations in the genes that regulate proliferation and differentiation of the putative stem cells, possibly located in the bulge region of the hair follicle,3 could give rise to different combinations of adnexal skin tumors.1,2,17-19 More recently, spiradenomas have been proposed to be apocrine tumors on the basis of adnexal morphogenesis and their close association with follicular and apocrine tumors in BSS.10 The morphogenesis of both apocrine and sebaceous glands is dependent on the hair follicle because the glands develop from epithelial buds arising directly above the isthmus. However, eccrine glands develop from the base of the interfollicular rete ridges of embryonic skin. Cylindromas and spiradenomas are not eccrine tumors but neoplasms of the folliculosebaceousapocrine unit, as demonstrated by the occurrence of sebaceous and trichoblastic differentiation in spiradenocylindromas. It is hypothesized that cylindromas and spiradenomas may be polar extremes of a spectrum of adnexal neoplasms with apocrine differentiation.13 Since the initial observation of mutations in the CYLD1 gene as cause for BSS,15 a host of different mutations have been reported, including frameshift mutations,1,20 splice site mutations,1 small deletions and insertions,1,15,21 and novel missense mutations.8 Most mutations lead to a premature translational stop, which disrupts the protein function.21 The CYLD gene interacts with several members of the nuclear factor-κΒ signaling pathway, which play important roles in inflammation, immune response, and oncogenesis. Inhibition of the CYLD gene enhances activation of the transcription factor nuclear factor-κΒ and leads to increased resistance to apoptosis and advanced carcinogenesis,21 which also results in compromise of the early steps in the development of epidermal appendages, including hair follicles and sweat glands.22 The exact mechanisms of CYLD-dependent tumorigenesis in the skin remain to be established. Cylindromas located on the head and neck region may eventually cover the entire scalp, resulting in so-called turban tumors.8 Mutational screening for the CYLD gene is beneficial to patients with multiple cylindromas and/or trichoepitheliomas as well as their family members. Physicians caring for patients and family members affected with BSS should contact the medical genetics department of their respective local medical school or academic medical center. Early identification of mutation carriers and appropriate genetic counseling may improve the therapeutic management to avoid complications such as disfigurement (turban tumor) or malignant transformation.21 Excision of all cylindromas and spiradenomas is recommended due to the low risk for malignant potential (cylindrocarcinoma and spiradenocarcinoma).8 If untreated, BSS can cause considerable disfigurement and discomfort, and severely neglected cases may require scalp surgery and reconstruction.23 Additionally, laser treatments, such as CO2 and erbium:YAG lasers, have been used for surgical destruction of several of the adnexal tumors (cylindromas and trichoepitheliomas), though the former ideally should be excised for histology because of the low risk for malignant transformation.5,9 Dermabrasion, chemical peels, electrodesiccation, and cryotherapy also may be considered as alternative treatment modalities.9 Brummelkamp et al24 demonstrated that inhibitory effects caused by CYLD gene mutations potentially can be reversed by application of salicylates or prostaglandin A. This discovery may give hope for novel therapeutic approaches in the future. The presence of pegged (conical) teeth in our patient is unusual, as this finding has not been described in BSS. The question remains, are these truly pegged teeth, and if so, is it merely an incidental (idiopathic) finding or rather part of an altogether new syndrome? As a result, genetic testing is extremely inviting.

Conclusion
Brooke-Spiegler syndrome consists of the classic triad of cylindromas, trichoepitheliomas, and spiradenomas. Mutations occur in the CYLD gene on band 16q12-13. Brooke-Spiegler syndrome is theorized as reflecting genetic dysfunction in the regulation of the folliculosebaceousapocrine unit. Early diagnosis is important with confirmatory genetic testing of the patient and family members. Further studies including genetic testing will need to be conducted to determine the relationship between pegged (conical) teeth and BSS.

Musicians are at risk for developing instrument-associated dermatologic conditions. The cutaneous problems are frequently secondary to abnormalities of saliva production, contact dermatitis, hyperhidrosis, infection, or physical trauma.1-10 Harpist's finger is reported in a beginner harpist who developed a trauma-induced blister on the finger she repetitively used to play her instrument. Skin problems in musicians caused by string instruments are reviewed.

Case Report
A healthy 6-year-old Chinese girl presented with a blister on her left index finger. She did not have a history of skin fragility or bullous skin disorders. Clinical evaluation revealed an 8X6-mm tense, tender, fluid-filled vesicle on the distal ventral pad of her left index finger. Additional questioning revealed that she had recently begun playing the harp and was playing the notes by plucking the strings with her fingers (Figure). Her wooden harp (an Allegro) was made of solid Honduras mahogany with a birch-laminated soundboard and finished with a water-white precatalyzed nitrocellulose lacquer with a semigloss (50%) sheen (unicoat). The nylon strings were either monofilament or wound (nylon wrap over nylon). The red (C musical note) and blue strings (F musical note) were created by placing the nylon strings in boiling water that was used to dissolve scarlet or navy blue dye powder (Rit® dye), respectively.

The diagnosis of a blister secondary to repeated trauma between her distal digit and the taut harp strings was established based on the correlation of the patient's history and clinical findings. The blister subsequently flattened and its roof spontaneously shed. The girl continued to play the harp and eventually developed a callus at this location on her finger. 

Comment
Dermatologic conditions in musicians that are caused by the instruments they play are frequently observed in orchestra members. Rimmer and Spielvogel1 distributed a survey regarding skin problems to 84 members of a professional symphony orchestra; 22 of 24 musicians who replied had instrument-associated dermatologic conditions. Intrigued by this study, Nethercott and Holness2 administered a health questionnaire to 41 orchestra members; 8 musicians reported a current work-related skin problem. More recently, Onder et al3 distributed a questionnaire to 97 orchestra members; 40 of 47 musicians who claimed to have either prior or current skin problems considered their dermatoses to be directly related to instrument use. Instrument-related skin conditions in musicians have been designated using several different classifications. Some of the conditions are described by their mechanism of pathogenesis and the resulting problem. For example, pizzicato paronychia is an infection of the nail fold in string players resulting from pizzicato playing whereby the musician plucks the instrument's strings instead of using a bow.4 Other dermatologic conditions in musicians are designated by combining the name of the instrument with either the anatomic location of the problem (eg, harpist's finger) or the description of the dermatosis (eg, piano paronychia). Alliteration often is incorporated into the nomenclature when these conditions are described, such as cellist's chest, clarinetist's cheilitis, drummer's digits, fiddler's fingers, guitarist's groin, piano paronychia, and pizzicato paronychia.1-6Harpists may develop calluses on the sides and tips of their fingers (harpist's finger), resulting from pressure and friction between the harpist's fingers and the strings of the instrument. The calluses may be painful or become irritated. Similar to the reported beginner harpist, neophyte harpists are especially susceptible to finger injury, such as sore fingertips and blister formation, prior to the development of calluses. Gradually increasing the time devoted to practicing the harp may enable the beginner harpist to avoid these problems.1,2,4,6,7,9,11 Harpists also are at risk for developing other instrument-associated dermatologic conditions, including not only intracorneal hemorrhage of the fingertips, similar to the friction-induced bleeding within the upper epidermis observed on the toes of runners (talon noir), but also nail dystrophies. Loosening of the nail plates and onycholysis may result from repetitive glissando playing in which the harpist rapidly glides one or more fingertips across multiple consecutive strings. In addition, paronychia, such as pizzicato paronychia from plucking the strings, and subungual hemorrhage with hematoma formation are other nail-related problems in harpists.1,4,6,7,9,11-13 Allergic contact dermatitis also has been observed, albeit rarely, in harpists. A 25-year-old woman who was a harpist developed an eczematous eruption of 5 months' duration on the fingertips of her right hand.2 Patch testing documented a 2+ reaction to potassium dichromate. Additional investigation revealed that this allergen was used as a tanning agent for the harp strings.2 Instrument-associated skin maladies also have been described in individuals playing other string instruments (Table).1-20 The main causes for these dermatoses are allergic contact dermatitis and physical trauma. The most common allergens associated with string instruments are chromium, nickel, colophony, paraphenylenediamine, propolis, and exotic woods.1-3,5-8,15,16,20

The 2 metallic substances, chromium and nickel, have been observed as allergens in musicians who play cello, guitar, harp, sitar, and violin. Allergic contact dermatitis to chromium has been described in electric guitarists, caused by contact with chromated steel components of their instruments, such as the strings, bridge, and frets, as well as the chromated leather accessories such as the guitar strap; a harpist for whom the allergen was used as a tanning agent for the harp strings; and a violinist whose E string was gold plated surrounding a chromated steel core.2,6,16 Nickel-related contact dermatitis has been described in a cellist whose wooden bow handle contained nickel, guitarists whose guitar strings contained the allergen, sitarists from the nickel mizrab covering the right index finger, and a violinist from the metal clamp of the violin's chin rest.1,3,6,8,20 Colophony (rosin) is a naturally occurring complex mixture of resin acids and neutral substances obtained from different species of coniferous trees (family Pinaceae). The principal sensitizer of colophony is abietic acid and its derivatives. Allergic contact dermatitis to colophony has been observed in cellists, violinists, and viola players who apply rosin to wax the strings on the bows of their instruments.1-8,15 Paraphenylenediamine is not only a skin sensitizer but also a skin irritant. Its principal use is in cosmetics as a black hair dye ingredient. Patch testing with a positive reaction to paraphenylenediamine was observed in an 11-year-old girl who had a cello with a black-string bow. She presented with scaling on her right thumb, index finger, and middle finger. A positive patch test result for paraphenylenediamine also was noted in a violinist who developed cutaneous eruptions located on his neck where it came into contact with the instrument's black chin rest.5-7 Propolis, also known as bee glue, has been reported to cause allergic contact dermatitis not only in musicians, such as cellists and violinists, but also in instrument makers. It can be found in many products of everyday use, such as chewing gum, facial creams, mouthwash preparations, and toothpastes. In addition, propolis is used as an ingredient in violin varnish.6,7 Exotic woods occasionally are used in the construction of the fingerboards of guitars and the body and/or chin rests of violas and violins. In string instruments, allergic contact dermatitis has been attributed to Brazilian rosewood (Dalbergia nigra), Indian rosewood (Dalbergiones species), East Indian rosewood (Dalbergia latifolia Roxb.), and ebony (Diospyros species) in chin rests and Makassar ebony in a violin. Because boxwood (Buxus sempervirens) does not contain any known allergens, it has been suggested as an alternative chin rest wood for musicians with allergic contact dermatitis to the wooden chin rest of their instrument.1,5-8 Physical trauma in musicians who play string instruments can result from the instrument or its strings. Dermatologic problems can be the sequelae of string instrument–induced physical trauma caused by the interaction of the fingers with the strings, which results in acro-osteolysis; callosities, such as harpist's fingers; Garrod pads; and nail dystrophies. Alternatively, mechanical trauma–associated skin conditions can occur secondary to pressure of the instrument against either the neck, chest, groin, knee, nipple, proximal arm, or scrotum.1,3-7,9,11-14,17-20

Conclusion
Musicians who play string instruments, such as the cello, guitar, harp, sarod, sitar, viola, and violin, can develop skin problems that usually result from either allergic contact dermatitis or physical trauma. The most common allergens are chromium, nickel, colophony, paraphenylenediamine, propolis, and exotic woods. Trauma-associated skin conditions are caused by either the interaction of the musician's fingers with the strings or pressure of the instrument against the musician's body. Harpist's finger is an example of a trauma-induced dermatologic problem, presenting as a callus on the affected finger, which may be preceded by soreness and blister formation that can be observed in beginner harpists.

Musicians are at risk for developing instrument-associated dermatologic conditions. The cutaneous problems are frequently secondary to abnormalities of saliva production, contact dermatitis, hyperhidrosis, infection, or physical trauma.1-10 Harpist's finger is reported in a beginner harpist who developed a trauma-induced blister on the finger she repetitively used to play her instrument. Skin problems in musicians caused by string instruments are reviewed.

Case Report
A healthy 6-year-old Chinese girl presented with a blister on her left index finger. She did not have a history of skin fragility or bullous skin disorders. Clinical evaluation revealed an 8X6-mm tense, tender, fluid-filled vesicle on the distal ventral pad of her left index finger. Additional questioning revealed that she had recently begun playing the harp and was playing the notes by plucking the strings with her fingers (Figure). Her wooden harp (an Allegro) was made of solid Honduras mahogany with a birch-laminated soundboard and finished with a water-white precatalyzed nitrocellulose lacquer with a semigloss (50%) sheen (unicoat). The nylon strings were either monofilament or wound (nylon wrap over nylon). The red (C musical note) and blue strings (F musical note) were created by placing the nylon strings in boiling water that was used to dissolve scarlet or navy blue dye powder (Rit® dye), respectively.

The diagnosis of a blister secondary to repeated trauma between her distal digit and the taut harp strings was established based on the correlation of the patient's history and clinical findings. The blister subsequently flattened and its roof spontaneously shed. The girl continued to play the harp and eventually developed a callus at this location on her finger. 

Comment
Dermatologic conditions in musicians that are caused by the instruments they play are frequently observed in orchestra members. Rimmer and Spielvogel1 distributed a survey regarding skin problems to 84 members of a professional symphony orchestra; 22 of 24 musicians who replied had instrument-associated dermatologic conditions. Intrigued by this study, Nethercott and Holness2 administered a health questionnaire to 41 orchestra members; 8 musicians reported a current work-related skin problem. More recently, Onder et al3 distributed a questionnaire to 97 orchestra members; 40 of 47 musicians who claimed to have either prior or current skin problems considered their dermatoses to be directly related to instrument use. Instrument-related skin conditions in musicians have been designated using several different classifications. Some of the conditions are described by their mechanism of pathogenesis and the resulting problem. For example, pizzicato paronychia is an infection of the nail fold in string players resulting from pizzicato playing whereby the musician plucks the instrument's strings instead of using a bow.4 Other dermatologic conditions in musicians are designated by combining the name of the instrument with either the anatomic location of the problem (eg, harpist's finger) or the description of the dermatosis (eg, piano paronychia). Alliteration often is incorporated into the nomenclature when these conditions are described, such as cellist's chest, clarinetist's cheilitis, drummer's digits, fiddler's fingers, guitarist's groin, piano paronychia, and pizzicato paronychia.1-6Harpists may develop calluses on the sides and tips of their fingers (harpist's finger), resulting from pressure and friction between the harpist's fingers and the strings of the instrument. The calluses may be painful or become irritated. Similar to the reported beginner harpist, neophyte harpists are especially susceptible to finger injury, such as sore fingertips and blister formation, prior to the development of calluses. Gradually increasing the time devoted to practicing the harp may enable the beginner harpist to avoid these problems.1,2,4,6,7,9,11 Harpists also are at risk for developing other instrument-associated dermatologic conditions, including not only intracorneal hemorrhage of the fingertips, similar to the friction-induced bleeding within the upper epidermis observed on the toes of runners (talon noir), but also nail dystrophies. Loosening of the nail plates and onycholysis may result from repetitive glissando playing in which the harpist rapidly glides one or more fingertips across multiple consecutive strings. In addition, paronychia, such as pizzicato paronychia from plucking the strings, and subungual hemorrhage with hematoma formation are other nail-related problems in harpists.1,4,6,7,9,11-13 Allergic contact dermatitis also has been observed, albeit rarely, in harpists. A 25-year-old woman who was a harpist developed an eczematous eruption of 5 months' duration on the fingertips of her right hand.2 Patch testing documented a 2+ reaction to potassium dichromate. Additional investigation revealed that this allergen was used as a tanning agent for the harp strings.2 Instrument-associated skin maladies also have been described in individuals playing other string instruments (Table).1-20 The main causes for these dermatoses are allergic contact dermatitis and physical trauma. The most common allergens associated with string instruments are chromium, nickel, colophony, paraphenylenediamine, propolis, and exotic woods.1-3,5-8,15,16,20

The 2 metallic substances, chromium and nickel, have been observed as allergens in musicians who play cello, guitar, harp, sitar, and violin. Allergic contact dermatitis to chromium has been described in electric guitarists, caused by contact with chromated steel components of their instruments, such as the strings, bridge, and frets, as well as the chromated leather accessories such as the guitar strap; a harpist for whom the allergen was used as a tanning agent for the harp strings; and a violinist whose E string was gold plated surrounding a chromated steel core.2,6,16 Nickel-related contact dermatitis has been described in a cellist whose wooden bow handle contained nickel, guitarists whose guitar strings contained the allergen, sitarists from the nickel mizrab covering the right index finger, and a violinist from the metal clamp of the violin's chin rest.1,3,6,8,20 Colophony (rosin) is a naturally occurring complex mixture of resin acids and neutral substances obtained from different species of coniferous trees (family Pinaceae). The principal sensitizer of colophony is abietic acid and its derivatives. Allergic contact dermatitis to colophony has been observed in cellists, violinists, and viola players who apply rosin to wax the strings on the bows of their instruments.1-8,15 Paraphenylenediamine is not only a skin sensitizer but also a skin irritant. Its principal use is in cosmetics as a black hair dye ingredient. Patch testing with a positive reaction to paraphenylenediamine was observed in an 11-year-old girl who had a cello with a black-string bow. She presented with scaling on her right thumb, index finger, and middle finger. A positive patch test result for paraphenylenediamine also was noted in a violinist who developed cutaneous eruptions located on his neck where it came into contact with the instrument's black chin rest.5-7 Propolis, also known as bee glue, has been reported to cause allergic contact dermatitis not only in musicians, such as cellists and violinists, but also in instrument makers. It can be found in many products of everyday use, such as chewing gum, facial creams, mouthwash preparations, and toothpastes. In addition, propolis is used as an ingredient in violin varnish.6,7 Exotic woods occasionally are used in the construction of the fingerboards of guitars and the body and/or chin rests of violas and violins. In string instruments, allergic contact dermatitis has been attributed to Brazilian rosewood (Dalbergia nigra), Indian rosewood (Dalbergiones species), East Indian rosewood (Dalbergia latifolia Roxb.), and ebony (Diospyros species) in chin rests and Makassar ebony in a violin. Because boxwood (Buxus sempervirens) does not contain any known allergens, it has been suggested as an alternative chin rest wood for musicians with allergic contact dermatitis to the wooden chin rest of their instrument.1,5-8 Physical trauma in musicians who play string instruments can result from the instrument or its strings. Dermatologic problems can be the sequelae of string instrument–induced physical trauma caused by the interaction of the fingers with the strings, which results in acro-osteolysis; callosities, such as harpist's fingers; Garrod pads; and nail dystrophies. Alternatively, mechanical trauma–associated skin conditions can occur secondary to pressure of the instrument against either the neck, chest, groin, knee, nipple, proximal arm, or scrotum.1,3-7,9,11-14,17-20

Conclusion
Musicians who play string instruments, such as the cello, guitar, harp, sarod, sitar, viola, and violin, can develop skin problems that usually result from either allergic contact dermatitis or physical trauma. The most common allergens are chromium, nickel, colophony, paraphenylenediamine, propolis, and exotic woods. Trauma-associated skin conditions are caused by either the interaction of the musician's fingers with the strings or pressure of the instrument against the musician's body. Harpist's finger is an example of a trauma-induced dermatologic problem, presenting as a callus on the affected finger, which may be preceded by soreness and blister formation that can be observed in beginner harpists.

Musicians are at risk for developing instrument-associated dermatologic conditions. The cutaneous problems are frequently secondary to abnormalities of saliva production, contact dermatitis, hyperhidrosis, infection, or physical trauma.1-10 Harpist's finger is reported in a beginner harpist who developed a trauma-induced blister on the finger she repetitively used to play her instrument. Skin problems in musicians caused by string instruments are reviewed.

Case Report
A healthy 6-year-old Chinese girl presented with a blister on her left index finger. She did not have a history of skin fragility or bullous skin disorders. Clinical evaluation revealed an 8X6-mm tense, tender, fluid-filled vesicle on the distal ventral pad of her left index finger. Additional questioning revealed that she had recently begun playing the harp and was playing the notes by plucking the strings with her fingers (Figure). Her wooden harp (an Allegro) was made of solid Honduras mahogany with a birch-laminated soundboard and finished with a water-white precatalyzed nitrocellulose lacquer with a semigloss (50%) sheen (unicoat). The nylon strings were either monofilament or wound (nylon wrap over nylon). The red (C musical note) and blue strings (F musical note) were created by placing the nylon strings in boiling water that was used to dissolve scarlet or navy blue dye powder (Rit® dye), respectively.

The diagnosis of a blister secondary to repeated trauma between her distal digit and the taut harp strings was established based on the correlation of the patient's history and clinical findings. The blister subsequently flattened and its roof spontaneously shed. The girl continued to play the harp and eventually developed a callus at this location on her finger. 

Comment
Dermatologic conditions in musicians that are caused by the instruments they play are frequently observed in orchestra members. Rimmer and Spielvogel1 distributed a survey regarding skin problems to 84 members of a professional symphony orchestra; 22 of 24 musicians who replied had instrument-associated dermatologic conditions. Intrigued by this study, Nethercott and Holness2 administered a health questionnaire to 41 orchestra members; 8 musicians reported a current work-related skin problem. More recently, Onder et al3 distributed a questionnaire to 97 orchestra members; 40 of 47 musicians who claimed to have either prior or current skin problems considered their dermatoses to be directly related to instrument use. Instrument-related skin conditions in musicians have been designated using several different classifications. Some of the conditions are described by their mechanism of pathogenesis and the resulting problem. For example, pizzicato paronychia is an infection of the nail fold in string players resulting from pizzicato playing whereby the musician plucks the instrument's strings instead of using a bow.4 Other dermatologic conditions in musicians are designated by combining the name of the instrument with either the anatomic location of the problem (eg, harpist's finger) or the description of the dermatosis (eg, piano paronychia). Alliteration often is incorporated into the nomenclature when these conditions are described, such as cellist's chest, clarinetist's cheilitis, drummer's digits, fiddler's fingers, guitarist's groin, piano paronychia, and pizzicato paronychia.1-6Harpists may develop calluses on the sides and tips of their fingers (harpist's finger), resulting from pressure and friction between the harpist's fingers and the strings of the instrument. The calluses may be painful or become irritated. Similar to the reported beginner harpist, neophyte harpists are especially susceptible to finger injury, such as sore fingertips and blister formation, prior to the development of calluses. Gradually increasing the time devoted to practicing the harp may enable the beginner harpist to avoid these problems.1,2,4,6,7,9,11 Harpists also are at risk for developing other instrument-associated dermatologic conditions, including not only intracorneal hemorrhage of the fingertips, similar to the friction-induced bleeding within the upper epidermis observed on the toes of runners (talon noir), but also nail dystrophies. Loosening of the nail plates and onycholysis may result from repetitive glissando playing in which the harpist rapidly glides one or more fingertips across multiple consecutive strings. In addition, paronychia, such as pizzicato paronychia from plucking the strings, and subungual hemorrhage with hematoma formation are other nail-related problems in harpists.1,4,6,7,9,11-13 Allergic contact dermatitis also has been observed, albeit rarely, in harpists. A 25-year-old woman who was a harpist developed an eczematous eruption of 5 months' duration on the fingertips of her right hand.2 Patch testing documented a 2+ reaction to potassium dichromate. Additional investigation revealed that this allergen was used as a tanning agent for the harp strings.2 Instrument-associated skin maladies also have been described in individuals playing other string instruments (Table).1-20 The main causes for these dermatoses are allergic contact dermatitis and physical trauma. The most common allergens associated with string instruments are chromium, nickel, colophony, paraphenylenediamine, propolis, and exotic woods.1-3,5-8,15,16,20

The 2 metallic substances, chromium and nickel, have been observed as allergens in musicians who play cello, guitar, harp, sitar, and violin. Allergic contact dermatitis to chromium has been described in electric guitarists, caused by contact with chromated steel components of their instruments, such as the strings, bridge, and frets, as well as the chromated leather accessories such as the guitar strap; a harpist for whom the allergen was used as a tanning agent for the harp strings; and a violinist whose E string was gold plated surrounding a chromated steel core.2,6,16 Nickel-related contact dermatitis has been described in a cellist whose wooden bow handle contained nickel, guitarists whose guitar strings contained the allergen, sitarists from the nickel mizrab covering the right index finger, and a violinist from the metal clamp of the violin's chin rest.1,3,6,8,20 Colophony (rosin) is a naturally occurring complex mixture of resin acids and neutral substances obtained from different species of coniferous trees (family Pinaceae). The principal sensitizer of colophony is abietic acid and its derivatives. Allergic contact dermatitis to colophony has been observed in cellists, violinists, and viola players who apply rosin to wax the strings on the bows of their instruments.1-8,15 Paraphenylenediamine is not only a skin sensitizer but also a skin irritant. Its principal use is in cosmetics as a black hair dye ingredient. Patch testing with a positive reaction to paraphenylenediamine was observed in an 11-year-old girl who had a cello with a black-string bow. She presented with scaling on her right thumb, index finger, and middle finger. A positive patch test result for paraphenylenediamine also was noted in a violinist who developed cutaneous eruptions located on his neck where it came into contact with the instrument's black chin rest.5-7 Propolis, also known as bee glue, has been reported to cause allergic contact dermatitis not only in musicians, such as cellists and violinists, but also in instrument makers. It can be found in many products of everyday use, such as chewing gum, facial creams, mouthwash preparations, and toothpastes. In addition, propolis is used as an ingredient in violin varnish.6,7 Exotic woods occasionally are used in the construction of the fingerboards of guitars and the body and/or chin rests of violas and violins. In string instruments, allergic contact dermatitis has been attributed to Brazilian rosewood (Dalbergia nigra), Indian rosewood (Dalbergiones species), East Indian rosewood (Dalbergia latifolia Roxb.), and ebony (Diospyros species) in chin rests and Makassar ebony in a violin. Because boxwood (Buxus sempervirens) does not contain any known allergens, it has been suggested as an alternative chin rest wood for musicians with allergic contact dermatitis to the wooden chin rest of their instrument.1,5-8 Physical trauma in musicians who play string instruments can result from the instrument or its strings. Dermatologic problems can be the sequelae of string instrument–induced physical trauma caused by the interaction of the fingers with the strings, which results in acro-osteolysis; callosities, such as harpist's fingers; Garrod pads; and nail dystrophies. Alternatively, mechanical trauma–associated skin conditions can occur secondary to pressure of the instrument against either the neck, chest, groin, knee, nipple, proximal arm, or scrotum.1,3-7,9,11-14,17-20

Conclusion
Musicians who play string instruments, such as the cello, guitar, harp, sarod, sitar, viola, and violin, can develop skin problems that usually result from either allergic contact dermatitis or physical trauma. The most common allergens are chromium, nickel, colophony, paraphenylenediamine, propolis, and exotic woods. Trauma-associated skin conditions are caused by either the interaction of the musician's fingers with the strings or pressure of the instrument against the musician's body. Harpist's finger is an example of a trauma-induced dermatologic problem, presenting as a callus on the affected finger, which may be preceded by soreness and blister formation that can be observed in beginner harpists.