[Close correlations between CD20 expression, a small mature plasma cell morphology and t(11 ; 14) in multiple myeloma].

Stratification of patients with multiple myeloma (MM) may be important. We investigated 138 MM patients, focusing on correlations between CD20 expression, 11 ; 14 translocation, morphology of MM cells, cyclin D1 immunostaining, and the prognosis. About 15% of patients (7/47cases) were CD20-positive, small mature MM cells, with positive cyclin D1 in the nucleus and 11; 14 translocation. Two color analysis of CD38 x CD20 antigens may be necessary to investigate CD20 expression on MM cells. Rituximab may be effective for the treatment of CD20-positive MM.