Clinical , Morphological , and Cell Kinetic Differences Among Multiple Myeloma , Monoclonal Gammopathy of Undetermined

We reviewed the clinical and morphological findings in 43 cases of monoclonal gammopathy of undetermined significance (MGUS). 9 of smoldering multiple myeloma (5MM). and 23 of overt multiple myeloma (MM). In all cases. the patients physicians had requested a bone marrow examination because of the possibility of MM. In all 75 cases. 3H-thymidine labeling indices were performed. The plasma cell labeling index correctly classified 62 of the 75 cases (83%). A linear discriminant function combining the labeling index and percentage of plasma cells improved the accuracy to 92% (69/75). or to 95% (71 /75) if patients in whom MM developed within 6 mo were considered to have