Cytogenetic Heterogeneity in Chronic Lymphocytic Leukemia.

Abstract

Objectives: Chronic lymphocytic leukemia (CLL) is a malignancy identified by an increase in the number of lymphocytes in the blood. It is one of the most common adult leukemias. It is a heterogeneous clinical disease with changeable progression. Chromosomal aberrations play a significant role in predicting clinical outcomes and survival. Treatment strategies for each patient are determined by chromosomal abnormalities. Cytogenetic methods are sensitive procedures for detecting abnormalities in the genome. The aim of this study was to document the incidence of different genes and gene rearrangements in CLL patients by comparing conventional cytogenetic and fluorescence in situ hybridization (FISH) results and predicting their prognosis. Materials and Methods A total of 23 CLL patients, 18 men and five women with ages ranging from 45-75 years were enrolled in this case series. Interphase fluorescent in situ hybridization (I-FISH) was conducted on peripheral blood or bone marrow samples, whichever were available, and were cultured in growth culture medium. I-FISH was used to detect chromosomal abnormalities such as 11q-, del13q14, 17p-, 6q- and trisomy 12 in CLL patients. Results FISH results showed that there were different chromosomal gene rearrangements including del13q, del17p, del6q, del11q, and trisomy 12. Recurrent chromosomal abnormalities involved trisomy 12, del17p, del13q and novel translocation (8;17) were only seen in one patient. Conclusion Genomic aberrations in CLL are important independent predictors of disease progression and survival. Interphase cytogenetic analysis using FISH revealed chromosomal changes in the majority of CLL samples and is superior to standard karyotype analysis for identifying cytogenetic abnormalities.