Background. The B-chronic lymphocytic leukemia (B-CLL) has highly variable prognosis. Possibility of more relevant prognosis has a great impact for the beginning and mode of therapy. Methods and Results. One hundred patients diagnosed as having B-CLL were included into the study. Beside usual examinations necessary to establish the diagnosis, cytogenetic examination for the detection of deletion 13q14, 17p13, 11q23 and trisomy 12 and immunophenotyping was done. The mean age of the patients was 58,2 years, there were 62 men and 38 women. 91 evaluated patients were divided into two groups – those with the steady disease (55 pts) and those with progressive disease (36 pts). No relation between the number of cytogenetic abnormalities and the Rai stage of the disease was found. We identified a relation between the bone marrow infiltration pattern (diffuse) and the number of cytogenetic abnormalities and the del 13q14 (p.05). Using the immunophenotyping of the lymphocytes we found a relation between the expression of CD38 and CD11c and the disease progression (p<0,05). Neither of the method (FISH and immunophenotyping) revealed differences between results from bone marrow samples and those from peripheral blood. Conclusions. Though the cytogenetic (FISH) and immunophenotype evaluation at the time of diagnosis did not improve the ability to define better the clinical course of the B-CLL, we suggest to use both methods routinely as an important tool to identify patients who would develop the progressive disease.

        Key words: Chronic lymphocytic leukemia B type (B-CLL), prognosis, fluorescence in situ hybridisation (FISH), imunofenotypisation.