Cytogenetic and Molecular Cytogenetic Investigations in Relapse of B-Cell Chronic Lymphocytic Leukemia

摘要

Chromosomal abnormalities have been analyzed in bone marrow cells of 61 patients with relapse of B-cell chronic lymphocytic leukemia. The cytogenetic results have allowed the structural stratification of the obtained karyotypes into ten groups of clones: normal, normalear tetraploid, abnormalormal, abnormalear tetraploidormal, evolution of clonal chromosome abnormalities; evolution of clonal chromosome abnormalitiesormal, evolution of clonal chromosome abnormalitiesear tetraploidormal, independent clones, independentormal clones; and independentear tetraploidormal clones. The identified structural rearrangements included translocations, deletions, insertions, and duplications; however, deletions with the involvement of bands 17p12, 13q12-q14, 11q14, and 11q23 dominated (63.8%). The application of i-FISH helped to show the presence of one to four abnormalities per karyotype. The identified cytogenetic and molecular cytogenetic rearrangements may signify a multilevel nature of the process underlying the development of resistant karyotypes. The results obtained under both methods have revealed the presence of a heterogenic cell population with possibly different levels of chemotherapy resistance.