Mycosis fungoides-like lesions associated with phenytoin therapy.

An 83-year-old woman developed generalized lymph node hyperplasia together with mycosis fungoides-like skin lesions 11 months after institution of anticonvulsant therapy with phenytoin. The clinicopathological changes disappeared completely three weeks after cessation of therapy. This circumstantial evidence together with the known data on the association of phenytoin with lymphoproliferative disorders suggest that it was the phenytoin that was responsible for the patient's condition. This case had features similar to those associated with the pseudo-mycosis fungoides syndrome except that the cutaneous lesions consisted of two localized erythematous plaques, with no generalized exfoliative erythrodermic dermatitis. Nonetheless, we believe that the use of the term pseudo-mycosis fungoides for this and similar cases would be appropriate.