A 66-year-old man visits the clinic seeking removal of a lesion on his nose that had been present for about 2 years. Recently, the growth had started to increase in size, prompting the patient’s visit. The patient has no history of skin or other cancers and has been using metronidazole gel on his nose to manage rosacea. On physical examination, a 0.8 cm firm, flesh-colored nodule is observed, with no similar lesions noted elsewhere on the body.
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Trichoepitheliomas are benign neoplasms originating within hair follicles and may resemble basal cell carcinoma both clinically and histopathologically.1 Solitary lesions typically appear on the face in adulthood as flesh-colored, asymptomatic papules or nodules.2 Dermoscopy may reveal arborizing vessels, multiple milia-like cysts, and rosettes against a whitish background.3 Complete excision of the lesions is the preferred removal technique to prevent recurrence.4
Trichoepitheliomas can be associated with multiple familial trichoepithelioma syndrome and the Brooke-Spiegler syndrome, both of which are transmitted as autosomal dominant traits with lesions first appearing during childhood.5,6 Malignant transformation has been reported but is quite rare.6
A shave biopsy of the patient’s lesion confirmed the diagnosis of trichoepithelioma. The histology showed a well-circumscribed dermal tumor consisting of nests and strands of basaloid cells in a retiform configuration.
Stephen Schleicher, MD, is director of the DermDox Dermatology Centers, associate professor of medicine at Geisinger Commonwealth Medical College, and clinical instructor of dermatology at Arcadia University and Kings College.
- Stanoszek LM, Wang GY, Harms PW. Histologic mimics of basal cell carcinoma. Arch Pathol Lab Med. 2017;141(11):1490-1502. doi:10.5858/arpa.2017-0222-RA
- Schukow C, Ahmed A. Trichoblastoma and trichoepithelioma. In: StatPearls [Internet]. StatPearls Publishing; Updated March 4, 2023. Accessed July 25, 2023.
- Sharma S, Chauhan P, Kansal NK. Dermoscopy of trichoepithelioma: a clue to diagnosis. Indian Dermatol Online J. 2018;9(3):222-223. doi:10.4103/idoj.IDOJ_146_17
- Karikal A, Shetty P, Karikal A, Shetty SR. Multiple trichoepitheliomas: a rare occurrence. South Asian J Cancer. 2013;2(2):54. doi:10.4103/2278-330X.110479
- Vy M, Mehrzad M, Konia T, Burrall B. An unusual case of multiple grouped non-familial trichoepitheliomas. Dermatol Online J. 2021;27(5). doi: 10.5070/D327553615
- Lee KH, Kim JE, Cho BK, Kim YC, Park CJ. Malignant transformation of multiple familial trichoepithelioma: case report and literature review. Acta Derm Venereol. 2008;88(1):43-46. doi:10.2340/00015555-0322. PMID: 18176750