Clinical significance of chromosomal abnormalities detected by interphase fluorescence in situ hybridization in newly diagnosed multiple myeloma patients.

Background Chromosome 13q14 deletion (del13q14), chromosome 1q21 gain (amp1q21) and chromosome 17p13 deletion (del17p13) are the most frequent chromosomal aberrations in multiple myeloma (MM). They play an important role in prognosis. The aim of this study was to investigate the clinical significance of the chromosomal changes in Chinese MM patients. Methods Interphase fluorescence in situ hybridization (FISH) on bone marrow (BM) cells was performed in 72 enrolled MM patients. Relationships between chromosomal abnormalities and clinical features, response to therapies and prognosis were analyzed. Results As a result of interphase FISH, 77.8% (56/72) patients had chromosome changes. The incidences of each probe were RB1 51.4% (37/72), D13S319 47.2% (34/72), 1q21 45.8% (33/72) and p53 22.2% (12/72). Osteolytic lesion, BM plasma cells index, serum calcium and serum M component were significantly correlated to del13q14. BM plasma cells and hemoglobin were correlated to amp1q21. Serum lactate dehydrogenase (LDH) was correlated with del17p13. Patients with del13q14 treated with bortezomib had a notably higher overall response rate than the patients treated with traditional chemotherapies (93% vs. 65%, P=0.048). Patients carrying amp1q21 or/and del17p13 did not achieve satisfactory response to bortezomib. The median progression-free survival (PFS) for patients with amp1q21 was 5 months and patients without amp1q21 got 9-month PFS (P=0.001). The median PFS for patients with del13q14 was 5 months (vs. 8 months, P=0.026). The median PFS for patients with del17p13 was 3 months (vs. 8 months, P=0.002). Patients with beta(2)-microglobulin >5.5 mg/L also had a worse outcome, whose median PFS was 5 months (vs. 8 months, P=0.016). Conclusions The prevalence of chromosomal abnormalities of MM patients was similar in Chinese and Caucasian people. Genetic changes were associated with patients' responses to therapies and prognosis. Chin Med J 2011;124(19):2981-2985