Asymptomatic multiple myeloma with concomitant neoplasms of two different origins.

A 63-year-old Japanese male with a four-year history of asymptomatic hypogamma-globulinemia is presented. On admission, he had a mild bone marrow plasmacytosis at about 10% of the total nucleated cells, but had no anemia, no paraproteins nor bone lesions. Flow cytometric analysis showed a predominant proliferation of kappa chain-positive cells in the bone marrow and peripheral blood, and an increase in the proportion of natural killer cells in the peripheral blood. Furthermore, coexistent meningioma and transitional cell carcinoma of the bladder were subsequently found 9- and 15-months after the admission, respectively. We considered that a myeloma-induced, possible latent immunodeficiency may have allowed the additional tumor growth, and that this process may have been controlled by the cytotoxic subset of immune effector cells.