Chronic lymphocytic leukemia (CLL) is characterized by accumulation of monoclonal malignant B cells in blood, lymph nodes, liver, spleen, and bone marrow. These cells have a unique immunophenotype and biology. With time, patients may develop progressive lym-phocytosis, lymphadenopathy, hepatosplenomegaly, anemia, and thrombocytopenia. Prior to the availability of flow cytometry, cytogenetic, and molecular analyses, the diagnosis was made based on an elevated white blood cell count with morphologic examination of the blood smear demonstrating characteristically small, well-differentiated lymphocytes. Some patients also presented with lymphadenopathy and/or hepatosplenomegaly. Flow cytometry has made evaluation and characterization of B-cell lymphoprolifera-tive diseases more precise and has enabled identification of subgroups of patients with clinically distinct diagnoses. Karyotypic analyses, including standard metaphase chromosome analysis and fluorescence in situ hybridization (FISH), have also been key in identifying subgroups of patients with B-cell lymphoprolif-erative diseases. Still, CLL remains a diagnosis for which diverse clinical courses are observed and are dictated by characteristics of the individual patients' leukemic clone. Continued work to identify important and significant prognostic factors will enable identification of clinical entities that represent distinct diseases within the group of patients currently diagnosed with CLL. In this chapter, we will review diagnostic criteria and clinical characteristics of patients with CLL.

0 0

Post a comment