CLINICAL SIGNIFICANCE OF DETECTION OF TUMOUR SUPPRESSOR GENE DELETION AT 12Q14 BY FISH TECHNIQUE IN CHRONIC LYMPHOCYTIC LEUKEAMIA

Abstract

Chronic lymphocytic leukemia is a neoplastic disease characterized by the accumulation of small mature appearing lymphocyte in the blood, marrow and lymphoid tissues, it accounts for approximately 0.8 % of all cancers and nearly 30 % of all leukemias.Generally, the neoplastic lymphocytes are of B­ cell lineage. In less than 2 percent of cases, however, the neoplastic cells are ofT-cell origin.

The malignant B-cell population in CLL consists of small round lymphocytes with regular nuclear and cytoplasmic out line and a clumped chromatin pattern.

Membrane characteristics of these cells include weak or negative surface imunoglobulin staining, CD5 positivity and FMC7 negativity. The cytogenetic abnormality of 13ql4 deletion with B-cell CLL form

20-25% ofCLL cases.

The aim of the present study was to demonstrate the incidence of 13ql4 deletion in B-CLL in Egyptian patients, and to use a new laboratory technique (FISH) in detection of 13ql4 deletion, in a way for better under standing of its clinico pathologic importance in such cases to demonstrate any correlation between 13ql4 deletion and the clinical picture of the patients and also if there is any correlation between 13ql4 deletion and the hematological finding.

study.

20 patients with B-CLL and I 0 control cases were included in the

They were subjected to clinical examina ion, routine laboratory investigation and immunophenotyping. Fluorescence in situ hybridization with