OBJECTIVETo explore the value of the technique of multiplex fluorescence in sit hybridization (M-FISH) combined with interphase fluorescence in situ hybridization (FISH) in the identification of the chromosomal aberrations in multiple myeloma (MM) and to investigate the frequency of 13q14 deletion, IgH translocations and 17p13 deletion.

METHODSSeven MM patients with complex chromosomal abnormalities (CCAs) were analyzed by combining the technique of conventional cytogenetics (CC) with M-FISH and FISH.

RESULTSM-FISH identified the aberrations which were undetected by CC, including twelve kinds of numeral aberrations and twenty-nine kinds of structural aberrations, In addition, abnormalities of chromosome 1, chromosomes 13 deletion and IgH translocations were the most frequent aberrations. Using the LSI D13S319 probe specific for 13q14, we observed a deletion of 13q14 in 6 MM patients; using the LSI p53 probe specific for 17p13, we observed p53 deletion in 4 MM patients; using the LSI IGHC/IGHV probe specific for 14q32, we observed a translocation involving 14q32 in 5 MM patients (43.5%), two translocations in two cases (case 6 and 7).

CONCLUSIONM-FISH combined with FISH could refine the cytogenetics of MM patients and detect the missed abnormalities or correct the misidentified abnormalities analyzed by CC. It provides an ideal method for the research of chromosomal aberrations in MM.