The importance of complex karyotype in prognostication and treatment of chronic lymphocytic leukemia (CLL): a comprehensive review of the literature.

Cytogenetic examination and the detection of chromosomal aberrations in chronic lymphocytic leukemia (CLL) is an integral part of prognostic stratification and treatment decisions. Improvements in cytogenetic methods, notably the introduction of the cell stimulation method, have led to the detection of chromosomal aberrations in 80% of CLL cases. A comprehensive analysis of cytogenetic aberrations recently showed that complex karyotypes (CKs) defined as the detection of either three or more or five or more chromosomal changes in a karyotype have a poor prognostic impact. The current efforts at the international level are focused on the goal of including CK assessment among prognostic markers for CLL patients at diagnosis as well as after treatment. This review of the literature documents the clinical importance of CK findings in CLL and the necessity of including this factor in other poor prognostic indicators.