AGGRESSIVE COURSE OF PRIMARY PLASMA-CELL LEUKEMIA WITH UNUSUAL MORPHOLOGICAL AND CYTOGENETIC FEATURES

A case of aggressive plasma cell leukemia with unusual morphological a nd cytogenetic features is reported. A 65-year-old man was admitted to hospital due to anemia, thrombocytopenia, and renal insufficiency. Bo ne marrow examination and peripheral blood smear revealed a large numb er of pleomorphic cells with convoluted and multilobulated nuclei. Imm unohistochemistry of the bone marrow biopsy was negative for anti-kera tin antibodies CAM.5.2 and AE1/AE3, but positive for EMA. The immunoph enotypic features of these cells were suggestive of plasma cell orgin with positivity for CD38, CD56, CD9, and CD44 and a weak positivity fo r CD71 and CD45 (40% of the cells), while all other markers of hematop oeitic origin were negative. Furthermore, a serum protein electrophore sis showed a monoclonal component type IgG-kappa of 70 g/l. The cytoge netic analysis demonstrated a hypotetraploid clone with multiple numer ical and structural abnormalities. Although some of the aberrations fo und are associated with plasma cell malignancies - e.g., structural re arrangement of chromosome 1, del(6q), and monosmy 13 - the karyotypic complexity in the present case is unusual. The course of the disease w as very aggressive, and the patient died 3 days after admission.