Chronic lymphocytic leukemia (CLL) and multiple myeloma (MM) are both lymphoproliferative disease occurring in different stages of B cell oncogeny. An increased incidence of secondary malignancies in patients with CLL is well recognized, however, the coexistence of both disorders in the same patient was very rare. Furthermore, clonal relationship between these diseases has not been clearly established. We report the occurrence of MM during the course of CLL. A 68-year-old patient was presented with general weakness and bone marrow aspiration showed a hypercellular marrow with 80% mature lymphocytes. At 5 months after diagnosis of CLL, bone marrow of the patient showed increased immature plasma cells. Serum protein electrophoresis showed monoclonal gammopathy and serum immunoelectrophoresis IgG kappa type monoclonality. The patient received six cycles of VAD (vincristine, adriamycin, dexamethasone) chemotherapy, but died of pneumonia and sepsis.

Keywords: Coexistence, Chronic lymphocytic leukemia, Multiple myeloma