A 60-year-old man presents requesting removal of a growth on his nose. The lesion has been present for at least 6 months and has remained asymptomatic; he occasionally plucks a white hair from the center. The patient has no history of skin or internal cancer. His family history is positive for colon and lung cancer. Examination reveals a well-defined 0.4 cm whitish papule with a minute central pore. No similar lesions are noted elsewhere.
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Biopsy of the lesion revealed a trichofolliculoma, an uncommonly encountered hamartoma of hair follicles. Trichofolliculoma most frequently arises on the face presenting as a dome-shaped, flesh-colored, or whitish papule ranging in diameter from 0.2 to 1.5 cm.1 Lesions may contain a central pit, thin wispy vellus hair, or tuft of fine, white wool-like hairs. Dermoscopy reveals an “erupting volcano” pattern about the dilated pore.2
Diagnosis is made by biopsy revealing numerous vellus hair follicles embedded in dense connective tissue.3 Histologic differential diagnosis includes basal cell carcinoma, fibrofolliculoma, and neurofollicular hamartoma.4
Unlike sebaceous adenoma and other facial hamartomas, trichofolliculomas are not associated with underlying malignancy or syndromes such as Birt-Hogg-Dube and Muir Torre. Only 1 case report hints at malignant transformation.5 Removal is accomplished by shave or surgical excision, although trichofolliculomas removed with surgical are more prone to recurrence.
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.
1. Massara B, Sellami K, Graja S, et al. Trichofolliculoma: a case series. J Clin Aesthet Dermatol. 2023;16(3):41-43.
2. Zhang LW, Li Y, Chen T, Xu RH. A case of trichofolliculoma with dermoscopy. Indian J Dermatol. 2023;68(1):107-108. doi:10.4103/ijd.ijd_51_23
3. Misago N, Kimura T, Toda S, Mori T, Narisawa Y. A revaluation of trichofolliculoma: the histopathological and immunohistochemical features. Am J Dermatopathol. 2010;32:35-43. doi: 10.1097/DAD.0b013e3181a77414
4. Emanuel P. Trichofolliculoma pathology. DermNet. Accessed June 5, 2023. https://dermnetnz.org/topics/trichofolliculoma-pathology
5. Stern JB, Stout DA. Trichofolliculoma showing perineural invasion. Trichofolliculocarcinoma? Arch Dermatol. 1979;115(8):1003-1004.