Primary plasma cell leukemia: morphologic, immunophenotypic, and cytogenetic features of 4 cases treated with chemotherapy and stem cell transplantation

Plasma cell leukemia (PCL) is a neoplastic disorder of plasma cells of which there are 2 forms, primary PCL and secondary PCL, the latter occurring in patients with a history of plasma cell myeloma. We describe 4 patients with primary PCL. In all cases, the bone marrow aspirate smears and biopsy specimens demonstrated a diffuse infiltrate of atypical plasma cells that were difficult to classify using morphologic criteria alone. Immunophenotypic studies showed that each case was positive for plasma cell–associated antigens (cytoplasmic immunoglobin, CD38, or CD138) and negative for CD20. Of 4 cases, 3 had complex karyotypes, including the t(11;14)(q13;q32) or del(11)(q13). Despite chemotherapy and the use of novel therapeutic agents and stem cell transplantation, all 4 patients had short survival.