Richter's Syndrome (RS) is a high-grade transformation that occurs in 5-15% of patients with B cell chronic lymphocytic leukaemia (B-CLL). RS is a complication of B-CLL in which the leukemia changes into a fast-growing diffuse large B cell lymphoma (DLBCL). The pathogenesis (mechanism by which the disease is caused) of RS is poorly understood and predictors of transformation and response to treatment are unknown. Management of RS remains unsatisfactory; the mean overall survival of patients treated with conventional chemo-immunotherapy such as CHOP-R is 8 months from the end of treatment.