Primary CNS lymphoma complicating treatment of myasthenia gravis with mycophenolate mofetil.

Mycophenolate mofetil (MM), an immunosuppressant used after organ transplantation, is also used for treatment of autoimmune myasthenia gravis (MG). A patient with generalized MG was effectively managed with MM but developed CNS lymphoma after 3 years of treatment. Primary CNS lymphoma regressed on withdrawal of MM. Despite minimal short-term side effects and apparent efficacy, chronic treatment of MG with MM may be associated with increased risk of lymphoproliferative disorders.