Treatment of Keratoacanthomas with Oral 13-cis-Retinoic Acid

KERATOACANTHOMAS are common cutaneous neoplasms that resemble squamous-cell carcinomas morphologically but behave in a biologically benign manner.1 A rare clinical manifestation of this neoplastic process is the Ferguson Smith variant, a type characterized by the progressive development of numerous lesions on almost any part of the cutaneous surface. Unlike solitary keratoacanthomas, those in multiplicity fail to resolve spontaneously, recur rapidly after surgical excision, and cause far greater morbidity. Such cases have previously been untreatable. We report a case successfully managed by surgery and the subsequent administration of 13-cis-retinoic acid by mouth, and discuss the pharmacology of this agent . . .