Snapshot quiz 14/5

Published: 04/11/2014

Authors: Brown C and Chamary V

This is an unusual presentation of a cutaneous horn in the natal cleft. Epidermal hyperkeratotic activity results in the conical protrusion of compacted keratin. Some 30 per cent of lesions are found on the face and scalp; other common sites include sun-exposed areas such as the chest and shoulder. The horn itself, although benign, can harbour premalignant and malignant epidermal lesions, including squamous and basal cell carcinomas. Associated premalignant and malignant lesions have been reported in up to 51 and 13 per cent of patients respectively. Given the neoplastic potential, formal excision biopsy is recommended.