Trichofolliculoma is a rare tumor of hair follicle origin. All 59 previously recorded cases of trichofolliculomas have been benign. In an occasional case, the tumor has recurred locally after surgical excision.
In this report, a case of trichofolliculoma showing perineural invasion is described, and the clinical importance of this observation is discussed.
Report of a Case
A 57-year-old man had a tender nodule on his left cheek immediately inferior to the lateral canthus. It had been present for eight months. No discharge or fine hairs were noted. The lesion was surgically excised.
Pathologic Findings
The tumor measured 1.6 cm in its greatest dimension and had a roughened, irregular, whitish surface with a tiny central depression.Microscopically (Fig 1), the tumor showed a large central keratin-filled cyst lined by squamous epithelium opening to the skin surface and extending into the dermis. At least three similar-appearing smaller cysts were present adjacent to