Malignant potential of keratoacanthoma.

Keratoacanthoma is generally considered to be a benign cutaneous lesion with initial rapid growth and spontaneous involution over several months. It is not generally appreciated that the keratoacanthoma may have a malignant potential or be associated with carcinoma. When a lesion diagnosed as keratoacanthoma recurs after excision, underlying malignancy must be considered. Four examples of keratoacanthoma associated with underlying malignancy are presented from the Ochsner Medical Institutions to emphasize the above points.