Leucémie lymphoïde chronique: Biologie et pronostic

B-cell chronic lymphocytic leukemia (CLL) is a clinically heterogeneous disease characterized by the accumulation of malignant CD5+B cells. Significant advances have occurred recently in our understanding of the genetic and molecular basis for the etiology and clinical course of CLL. A major observation has been that the B-cells in indolent types of CLL which do not require therapy, have undergone somatic hypermutation and function as memory B-lymphocytes whereas those more likely to progress have not undergone this process. Emerging data have been developed, describing new parameters less or more correlated with the types of somatic hypermutation, in particular ZAP-70 expression and telomere length. New evidence suggests the role of antigenic stimulation of the B-cell receptor (BCR) that induced proliferation of leukemic cells and allows them to avoid apoptosis. These different effects may explain the disparity in clinical outcomes among individual cases of CLL. The identification of genetic and molecular prognostic factors can be used in early-stage patients to identify those who will progress rapidly. Furthermore, these genetic- and molecular-based factors constitute targets of new treatment modalities. Altogether, the combination of our major advances in the understanding of the biology, immune status and the therapy of the CLL provides for the first time the opportunity for curative strategies.