BCR and B-cell chronic lymphocytic leukemia: Indeed, the study of major CLL stereotyped subsets has revealed that similarities between cases in a given subset extend beyond immunogenetic and other biological characteristics of the malignant clones (genomic aberrations, epigenomic status, BcR IG 3D conformation and signaling capacity) to disease course and outcome (108, 115, 120, 138–141).