Coincident chronic lymphocytic leukemia and osteosclerotic multiple myeloma

We report the first occurrence of chronic lymphatic leukemia (CLL) and osteosclerotic multiple myeloma (MM) in the same patient. The surface Ig of the CLL and the monoclonal serum Ig had different heavy and light chain classes, and CLL lymphocytes failed to secrete the monoclonal Ig in short-term culture. We conclude that they were entirely separate malignancies occuring together by chance.