Hypodiploidy is a major prognostic factor in multiple myeloma

Conventional karyotypes performed before any treatment in 208 patients with multiple myeloma were reviewed by the Groupe Francais de Cytogenetique Hem atologique. A total of 138 patients displayed complex chromosomal abnormali ties (CCAs). According to the chromosome number pattern, a first group of 7 5 patients had a hyperdiploid karyotype. A second group of 63 patients refe rred to as the hypodiploid group had either pseudodiploid, hypodiploid, or near-tetraploid karyotypes. Of 159 treated patients available for survival analysis, 116 had an abnormal karyotype. The comparison of overall survival (OS) between hyperdiploid and hypodiploid patients showed a highly signifi cant difference (median OS 33.8 vs 12.6 months, respectively, P < .001). Th e presence of 14q32 rearrangements (36 of 116 patients) worsened the progno sis (median OS 17.6 vs 29.9 months, P < .02). The presence of chromosome 13 q abnormalities (13qA, 63 patients) did not modify OS in CCA patients (medi an OS 20.6 vs 27.8 months, P < .59). However, taking into account the whole series including normal karyotypes, 13qA (63 of 159 patients) had a signif icant impact on OS (median 20.6 vs 37.1 months, P < .04). In the same way, the presence of a hypodiploid karyotype (52 of 159 patients) had a strong p rognostic value (OS 12.8 vs 44.5 months, P < .000 01). A multivariate analy sis including stage, beta (2)-microglobulin, bone marrow plasmocytosis, tre atment type, 13qA, and hyperdiploidy and hypodiploidy showed that a hypodip loid karyotype was the first independent factor for OS (P < .001), followed by treatment approach. These results confirm that the chromosome number pa ttern of malignant plasma cells is a very powerful prognostic factor in new ly diagnosed multiple myeloma patients. (C) 2001 by The American Society of Hematology.