Cytogenetic Characteristics Of Chronic Myeloid Leukemia

ObjectiveTo characterize the cytogenetic of chronic myeloid leukemia (CML).Methods1. To investigate the frequency of derivative chromosome 9 [der(9)] deletions in patients with chronic myeloid leukemia (CML), karyotype analysis was performed with R-banding technique in 138 patients with CML, and dual fusion fluorescence in situ hybridization (FISH) was used to detect der(9) deletion.2. To investigate the frequency of trisomy 8 in patients with CML, karyotype analysis was performed with R-banding technique in 75 patients with CML treated with imatinib, and FISH was used to detect trisomy 8.Results1. The results showed that 126 cases (8.7%) were Ph positive, 12 (8.7%) were Ph negative(BCR-ABL1 positive); 23 cases (16.7%) with der(9) deletions were detected by FISH technique, 20 of 122 patients with typical Ph translocation and 3 of 4 patients with variant Ph translocation.,20 cases in chronic phase (CP) (17.2%), 3 in blast crisis (BC) (17.6%). There was no significant difference in the frequency of the der (9) deletions between the cases in CP and those in BC(P<0.05).2. The results showed, by karyotype analysis, that 74 cases (98.7%) were Ph positive, 1 case (1.3%) were Ph negative(BCR-ABL1 positive); none with trisomy 8 were detected before treatment ;after treatment with imatinib,2 case(2.7%) with +8 was detected. By FISH technique, none with trisomy 8 were detected before treatment ;after treatment with imatinib,4 cases (5.4%) with +8 was detected;2 case of Ph negative, 2 cases of Ph positive.Conclusions1. It is concluded that deletions are detected in about 1/6 CML patients, FISH can effectively detect the der(9) deletions, and there is no correlation of der (9) deletion frequency between cases in different phases of CML.2. It is concluded that FISH can effectively detect +8 in CML patients, while +8 in Ph negative clone can not indicate the disease progression.