Immunoglobulin sequence analysis and prognostication in CLL: guidelines from the ERIC review board for reliable interpretation of problematic cases

prognostication in chronic lymphocytic leukemia (CLL) and the definition of standardized procedures has allowed reliable and reproducible results. Occasionally, a straightforward interpretation of the sequences is not possible because of the so-called 'problematic sequences' that do not fit the 'classic' interpretation and pose scientific questions at the cross-road between hematology and immunology. Thanks to a dedicated effort within the European Research Initiative on CLL (ERIC), we have now the possibility to present such cases, offer a scientific explanation and propose recommendations in terms of prognostication. Leukemia (2011) 25, 979-984; doi:10.1038/leu.2011.49; published online 1 April 2011