Giant keratoacanthoma-like cutaneous horn of the upper leg: A case report.

Giant cutaneous horns are suspicious of malignancy, in particular squamous cell carcinoma. We report on a 67-year-old man that developed a giant horn on his upper leg that resembled a keratoacanthoma. The lesion was surgically removed. Histologic investigation revealed a giant verruca vulgaris. No risk factors such as immunosuppression were evident. Giant verruca vulgaris is a very rare cause of giant cutaneous horns. Complete excision is recommended in order not to overlook a malignant skin tumor in such cases.