[Detection of Gene Abnormalities in 43 Cases of Chronic Lymphocytic Leukemia by Fluorescence in Situ Hybridization].

Objective: To explore the value of fluorescence in situ hybridization (FISH) in diagnosis and prognosis evaluation of chronic lymphocytic leukemia (CLL).

Methods: R banding technique was used for karyotype analysis in 43 cases of CLL, and fluorescence in situ hybridization（FISH） technique was used for analysis of 5 genes in 43 cases of CLL, including D13S25, RB1,ATM, P53 and CEP 12 .

Results: The detection rate of chromosome abnormality was 9.3％ for the 43 cases. The chromosome karyotype abnormality was involoved in the number abnormality and the structural abnormality, including No. 2, 6, 14, and sex chromosome. The patients with normal chromosome karyotype were more common（79.1％）. At the same time, mitotic figure in 5 CLL patients did not observed. The positive rate of FISH detection was 55.8％(24/43). Among which, D13S25 deletion was the highest and reached to 37.2％, followed by RB1 deletion（20.9％）, CEP 12 amplification（16.3％）, ATM deletion（9.3％） and P53 deletion（7.0％）. In 24 FISH-positive cases, 20 cases displayed the normal chromosome karyotype, and in 3 cases the mitotic figure was absent. There was only one case of abnormal chromosome, which was not involved in the positive gene tested by FISH.

Conclusion: FISH is an important means of CLL genetic detection, which can greatly raise the detection rate of cytogenetics abnormalities in CLL, but the probe quantity is limited, so it is necessary to use FISH technology combined with chromosome karyotype analysis so as to improve the detection rate of abnormal cytogenetics, and provide the basis for the clinical diagnosis and prognosis of CLL.