Seborrheic keratosis of the nasal vestibule.

Seborrheic keratosis is a common hyperkeratotic lesion of the epidermis, that usually occurs in the trunk and less frequently in the extremities, face, and the scalp. Occurrence in the nasal vestibule has not been reported in the literature. An 80-year-old woman presented with a long-standing, slowly growing, firm, red-brown polypoid mass, 0.5 cm in size, located at the skin-mucosa interface of the right nasal vestibule. The lesion was excised under local anesthesia and histopathologic examination showed seborrheic keratosis that mimicked squamous cell carcinoma. There was no recurrence during a-year follow-up.