Diagnosis: Keratoacanthoma and sebaceous adenoma in a patient with Muir-Torre syndrome.
MICROSCOPIC FINDINGS AND CLINICAL COURSE
Hematoxylin-eosin–stained sections of the forehead specimen showed a large tumor composed of nests of squamous epithelial cells. The lesion, which had a cup-shaped architecture and a central keratinous plug, consisted primarily of numerous islands of keratinizing epithelium that permeated the dermis. The largest keratinocytes contained ample amounts of "glassy" cytoplasm. No sebaceous differentiation was noted. The clinical and microscopic findings were consistent with a keratoacanthoma.
The second specimen showed a nodule with cells that demonstrated prominent cytoplasmic vacuolization consistent with sebaceous differentiation. Sebaceous glands contained within the neoplasm were moderately to well differentiated. The neoplasm consisted of an approximately equal proportion of basaloid cells and cells with vacuolated cytoplasm. These findings were most consistent with a sebaceous adenoma.
Biopsy specimens of additional yellowish papules on the face revealed similar histologic findings, which were also consistent with sebaceous adenoma. The kearatoacanthoma was treated by Mohs micrographic surgery. Over the next year, . . . [Full Text of this Article]
DISCUSSION
