Chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL) is the most common leukaemia in developed countries. It is a disease of the elderly, usually incurable and characterized by significant clinical and biological heterogeneity. Many patients are diagnosed after the incidental finding of a sustained lymphocytosis, while others present with symptomatic disease requiring treatment. Clinical features arise from immune dysfunction and tissue infiltration, and include fatigue, infections, lymphadenopathy, hepatosplenomegaly and cytopenias. Key diagnostic tests are peripheral blood morphology and immunophenotyping. Clinical staging, lymphocyte doubling time and biomarkers are useful in assessing prognosis. Overall, median survival is 10 years. Patients with CLL undergo regular monitoring, and therapy is reserved for those with symptomatic or rapidly progressive disease. Early intervention has no impact on outcome and can encourage drug resistance. Consideration must be given to the patient's fitness for treatment and the management of co-morbidities. Supportive care includes prevention and treatment of infection, transfusion support and treatment of autoimmune cytopenias. Chemo-immunotherapy continues to be the mainstay of front-line treatment for standard-risk disease. However, treatment of CLL has rapidly evolved over recent years with the introduction of targeted therapies that inhibit signalling downstream of the B cell receptor, second-generation monoclonal antibodies and BCL2B Cell Lymphoma 2 (BCL2) antagonists.