A 45-year-old man with familial multiple keratoacanthomas, acne conglobata, and hidradenitis suppurativa is presented. Healing of the keratoacanthomas was associated with oral administration of methotrexate. A brief survey of the histogenesis, possible etiologic factors, course, and treatment of the lesions is given. The pharmacology of folic acid inhibitors is reviewed briefly. Possible mechanisms of action of methotrexate in the disease are suggested, with particular emphasis on an admittedly speculative "antiviral" activity. Objections to attributing a cause and effect relation to methotrexate in healing of the lesions are discussed.
TARNOWSKI WM. Multiple KeratoacanthomataResponse of a Case to Systemic Chemotherapy. Arch Dermatol. 1966;94(1):74–80. doi:10.1001/archderm.1966.01600250080016
Customize your JAMA Network experience by selecting one or more topics from the list below.