Chronic Lymphocytic Leukemia

CLL is a malignant disease characterized by progressive accumulation of immature, immunophenotypically distinct lymphocytes in the blood, bone marrow, and lymphatic tissues. Although the clinical course of CLL can be unpredictable, this disease is typically slow-progressing and occurs most often in patients ≥65 years of age. As such, treatment, if indicated, is typically conservative. Current CLL treatments are not considered to be curative; however, long-term remission can be achieved in some patients using allogenic stem cell transplantation.

Chronic lymphocytic leukemia is characterized by the clonal proliferation and accumulation of small, mature-appearing CD5-positive B lymphocytes in the blood, bone marrow, and secondary lymphoid tissues. A CLL diagnosis is established by the presence of more than 5x109/L peripheral lymphocytes co-expressing CD5, CD19, and CD23, and weakly expressing CD20, CD79b, and surface immunoglobulin. Small lymphocytic lymphoma represents a clinical variant of CLL and is similarly managed.