[Simultaneous occurrence of acute myeloid leukemia with multilineage dysplasia and multiple myeloma]

An 82-year-old woman was admitted to our hospital because of dizziness and petechiae. Peripheral blood examination showed severe anemia and thrombocytopenia. Bone marrow aspiration revealed 42% leukemic blasts positive for peroxidase with multilineage dysplasia, leading to a diagnosis of acute myeloid leukemia with multilineage dysplasia. The levels of the patient's marrow plasma cells increased to 12%, whereas serum levels of IgG, A, and M dropped. lambda type Bence Jones protein was detected on urine immunoelectrophoresis. The total urinary protein was 3, 960 mg/day. Bone scintigraphy detected multifocal uptake in the ribs. The diagnosis was multiple myeloma developing simultaneously with acute myeloid leukemia. Possible mechanisms for the occurrence of acute myeloid leukemia and multiple myeloma were discussed.