Cutaneous lymphoma associated with Epstein-Barr virus infection in 2 patients treated with methotrexate.

Whether patients with rheumatoid arthritis (RA) have an increased risk of developing non-Hodgkin lymphoma is controversial, and opinions differ on the possible role of methotrexate in the occurrence of lymphomas in patients with RA. We report 1 T-cell lymphoma and 1 B-cell lymphoma restricted to the skin associated with Epstein-Barr virus infection that healed completely and spontaneously after discontinuation of methotrexate in a man with RA and a woman with dermatomyositis. Cutaneous infiltrating cells were infected by a replicative form of Epstein-Barr virus. After discontinuation of methotrexate, the cutaneous lesions disappeared completely in 15 days without recurrence. Discontinuation of methotrexate is necessary in patients with RA or dermatomyositis who have a lymphoproliferative disorder, and a follow-up period of several weeks should be observed before specific therapy is initiated.