SUMMARY. Analysis of bone marrow cells chromosomal abnor-malities in relspse of 61 patients with B-cell chronic lymphocytic leukemia were performed. Karyotypes ac-cording the clone structure were presented as 10 types: normal; normal/near tetraploid; abnormal/normal; abnormal/near tetraploid/normal; evolution of clonal abnor-malities; evolution of the clonal abnormalities/normal; evolution of the clonal abnormalities/near tetraploid/normal; independent clones; independent/normal; inde-pendent/near tetraploid/normal clones. Among the structural rearrangements the translocations, deletions, inser-tions, duplications were detected, however, deletions were dominated (63,8 %) involving the bands 17р12, 13q12-q14, 11q14 and 11q23. The compexity from one to four abnormalities in one karyotype was shown by i-FISH. Cytogenetic and molecular cytogenetic rearrangements may indicate a multilevel process of formation of resistant karyotypes. Presence of a heterogeneous population of cells with the possible varying degrees of resistance to chemotherapy was confirm by both methods.
Keywords: chronic lymphocytic leukemia, bone marrow cells, chromosomal abnormalities, relapse
