IMPROVED CYTOGENETIC ANALYSIS OF BONE-MARROW PLASMA-CELLS AFTER CYTOKINE STIMULATION IN MULTIPLE-MYELOMA - A REPORT ON 46 PATIENTS

Cytogenetic analysis was successfully performed in 46 consecutive myeloma patients (40 newly diagnosed and six relapsed patients). Karyotype was performed on bone marrow cells after long-term cultures (6 d) stimulated by GM-CSF, GM-CSF + IL6 or GM-CSF + IL6 + 11.3. Nineteen patients (41%) had cytogenetic abnormalities including 17/40 patients at diagnosis (42.5%) and 2/6 patients at relapse. Hyperdiploidy was found in 12 patients and hypodiploidy in four patients. Of the 17 newly diagnosed patients with cytogenetic abnormalities, five died from myeloma after 1-14 months and three other patients had primary drug resistance. Our results suggest that cytogenetic analysis after stimulation of cultures by cytokines detects clonal abnormalities in 40-50% of newly diagnosed myeloma patients and that these patients often have a short survival and/or primary drug resistance.