A case of severe aplastic anemia secondary to treatment with lenalidomide for multiple myeloma.

Lenalidomide is an important contemporary treatment option for patients with multiple myeloma (MM). Rare instances of autoimmune conditions have been observed in association with its use. Although moderate myelosuppression is not uncommonly seen in patients treated with lenalidomide, aplastic anemia has not previously been reported to be associated with this agent. We describe a case of severe aplastic anemia (AA) that was probably induced by lenalidomide. A 64-year-old male patient developed progressive pancytopenia three weeks into therapy with lenalidomide for his relapsed MM. A bone marrow aspirate and biopsy confirmed the diagnosis of AA and suggested the existence of an immunological reaction at the level of marrow. A gradual spontaneous recovery of normal hematopoiesis followed after the lenalidomide discontinuation.