Chronic lymphocytic leukaemia

Chronic lymphocytic leukaemia (CLL)/small lymphocytic lymphoma is the most prevalent lymphoid neoplasm in Europe and North America. The ‘cell of origin’ is a mature B lymphocyte with a rearranged immunoglobulin gene. CLL cells express modest amounts of surface immunoglobulin, and are characterized by defective apoptosis. The cause of CLL is unknown. Most patients show no specific clinical features of disease and are diagnosed during evaluation of an incidental finding of peripheral blood lymphocytosis, lymphadenopathy, or splenomegaly. A small percentage of patients (<10%) present with symptomatic disease resulting from (1) tissue accumulation of lymphocytes such as disfiguring lymphadenopathy, splenomegaly with abdominal discomfort, profound fatigue, drenching night sweats, weight loss, and fever; or (2) manifestations of marrow failure with cytopenias including anaemia and thrombocytopenia. All CLL patients have an increased risk of infection, autoimmune cytopenias, and second haematological (e.g. diffuse large B-cell lymphoma) and nonhaematological malignancies. Diagnosis is usually made by analysis of the immunophenotype of the monoclonal circulating cells in the peripheral blood. In patients with the small lymphocytic variant of CLL without a detectable circulating monoclonal B-cell population, the diagnosis is made using tissue from the bone marrow, lymph nodes, or spleen. Treatment—there is no standard curative therapy and patients should not be treated until they have progressive and symptomatic disease or develop anaemia or thrombocytopenia due to bone marrow failure. If a decision is made to treat, then the best initial treatment should be given, based on evaluation of the patient’s disease characteristics with specific attention to the integrity of TP53 (coding for p53) and patient fitness.