Richter transformation in Chronic Lymphocytic Leukemia.

Chronic lymphocytic leukemia can evolve to an aggressive lymphoma-in most of the cases diffuse large B cells lymphoma, rarely Hodgkin lymphoma-and this complication is defined Richter syndrome (RS). Immunogenotypic features that characterize RS include unmutated IgHV status with high prevalence of IgHV4-39/D6-13/J5 sequence; deletion of chromosome 17p or 11q; activation of oncogenes as NOTCH1 and c-MYC; inactivation of onco-suppressors as TP53 and CDKN2A; high expression of CD38 in lymph-nodes. The prognosis of this condition is very poor: patients experience a rapid clinical deterioration with frequent therapeutic failure since the current options include suboptimal strategies as standard chemo-immunotherapy followed by hematopoietic stem cells transplantation or enrollment in clinical trials which investigate the efficacy of target drugs. Understanding the biology of such a heterogeneous condition is crucial to personalize the treatment and improve patient's survival.