RESUMEN
To assess the incidence and prognostic significance of MYB gene [6q23] deletion among a sample of Egyptian B-chronic lymphocytic leukemia [B-CLL] patients and to con elate it with other established prognostic factors This study was conducted on 63 newly diagnosed Egyptian B-CLL patients attending Am Shams University Hospitals. Fluorescence in situ hybridization [FISH] using locus specific identifier MYB [6q23] probe was applied on peripheral blood/bone marrow samples and was correlated with different established prognostic factors. Follow up was done through a period of 48 months to evaluate disease outcome. 6 patients had MYB deletion. All of them showed lymphocyte doubling time [LDT] more than 12 months and were CD38 positive. 83 3% of patients were good responders to therapy and none of these I atents died. B-CLL patients who were positive for MYB [6q23] deletion represent a cytogenetic entity associated with CD38 positivity and LDT>12 months They were considered as an intermediate risk group