Chromosomal aberrations in chronic lymphocytic leukaemia, their prognostic and predictive role

Czech version

Authors: L. Krůzová; T. Papajík; H. Urbánková
Authors‘ workplace: Hemato-onkologická klinika Lékařské fakulty Univerzity Palackého v Olomouci a Fakultní nemocnice Olomouc
Published in: Transfuze Hematol. dnes,26, 2020, No. 1, p. 19-28.
Category: Review/Educational Papers

Overview

Chromosomal aberrations play an important role in the pathogenesis and development of chronic lymphocytic leukaemia (CLL). They characterize the course of the disease and influence decisions regarding treatment. Aberrations with well-known prognostic significance include deletions of regions 11q, 13q, 17p and trisomy of chromosome 12. The importance of other recurrent cytogenetic abnormalities, such as duplications of 2p or 8q24, deletion of 6q21, translocations of 14q32 and complex karyotype have recently come under closer scrutiny. Chromosome aberrations are detected by classical G-banding, fluorescent in situ hybridization (FISH) and in some cases by contemporary array comparative genomic hybridization (arrayCGH). The implementation of next generation sequencing (NGS) has helped identify new gene mutations (particularly TP53, NOTCH1, SF3B1 and BIRC3), which refine patient stratification and influence the choice of treatment strategy. In future, prognostic and predictive models resulting from the combination of all mentioned methods will better reflect disease dynamics and clonal evolution and lead to a more accurate assessment of treatment response and survival.

Keywords:

chronic lymphocytic leukaemia – prognostic factors – Cytogenetics – Fish – Chromosomal aberrations

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