A case of desmoplastic trichilemmoma of the lip treated with Mohs surgery

BACKGROUND. Desmoplastic trichilemmoma is a rare pseudomalignant variant of trichilemmoma. It generally presents as a small papule on the face and is often clinically misdiagnosed as a basal cell carcinoma or verruca vulgaris. It is histologically similar to a trichilemmoma, but has a central area of desmoplasia that can mimic an invasive carcinoma. OBJECTIVE. The objective was to report a case of desmoplastic trichilemmoma of the lower lip that was treated with Mohs micrographic surgery. METHODS. A case is reported and the literature is reviewed. RESULTS. The patient underwent Mohs micrographic surgery for removal of the neoplasm. Six months after the procedure, the patient remained tumor free. CONCLUSIONS. Although desmoplastic trichilemmoma is a benign neoplasm, it is often histologically confused with basal cell carcinoma and malignant trichilemmoma. Desmoplastic trichilemmoma is also most frequently located on the face. Considering these factors, Mohs micrographic surgery appears to represent an excellent choice for removal of these tumors to achieve clear margins and a good cosmetic result.