Cytogenetics in the management of chronic lymphocytic leukemia: an update by the Groupe francophone de cytogénétique hématologique (GFCH).

Acquired recurrent cytogenetic abnormalities are frequent in chronic lymphocytic leukaemia (CLL). They can be associated with good or poor prognostic factors, and also with gene mutations. Chromosomal abnormalities could be clonal or sub-clonal. Assessing the TP53 status (deletion/mutation) is currently mandatory before treating patients. The search for 11q deletion (ATM gene) is also recommended. Finally, the prognostic value of other chromosomal abnormalities including complex karyotype is still debated.