The development of B-cell lymphoma in a patient with psoriasis treated with cyclosporine.

A 67-year-old Nicaraguan man with a history of chronic, severe, recalcitrant psoriasis participated in a multicenter study investigating oral cyclosporine in the treatment of psoriasis. He received cyclosporine for approximately 8 months at doses of 5 mg/kg/day or less. Treatment with cyclosporine was eventually discontinued because of progressive nephrotoxicity. Approximately 7 months after the discontinuation of cyclosporine, the patient developed a mass in the left maxillary sinus extending to the orbit, the palate, and the infratemporal fossa. Pathologic and histochemical analysis of the mass revealed a B-cell lymphoma. The development of a benign lymphocytic infiltrate has been reported in a patient who received cyclosporine therapy for psoriasis; however, to the best of our knowledge, this is the first case in the United States of lymphoma developing in a patient who was treated with cyclosporine for a condition other than organ transplantation.