A Case of Inverted Follicular Keratosis Arising from Nevus Sebaceus / 대한피부과학회지

ABSTRACT

Inverted follicular keratosis is a benign epithelial tumor occurring most frequently on the face or scalp of older persons as a firm, skin-colored papule. It may rarely occur from a pre-existing nevus sebaceus as a secondary tumor. Herein we report a case of inverted follicular keratosis arising from a pre-existing nevus sebaceus in a 47-year-old male. He presented with a keratotic erythematous dome-shaped tumor which suddenly developed from a pre-existing yellowish papillomatous plaque on his scalp. Histopathological findings of the secondary lesion revealed a proliferating epithelial tumor with numous squamous eddies in the center, consistent with inverted follicular keratosis.