Staging and therapy of chronic lymphocytic leukemia.

Chronic lymphocytic leukemia (CLL) is a heterogeneous disease. Some patients require no therapy and have prolonged survival. Others have brief survival despite intensive treatment. Several staging systems have been developed. These are useful in predicting outcome and need of therapy, but controversies exist. Additional prognostic factors have been identified such as cytogenetics, lymphocyte levels or doubling time, bone marrow morphology, and others. Patients with low-stage CLL have not been shown to benefit from treatment. In patients with intermediate disease, combination chemotherapy with cyclophosphamide, vincristine, and prednisone (CVP) has not been shown to be superior to chlorambucil with or without prednisone. The therapy of high stage CLL is controversial; therapy with cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) may be superior to CVP. Future directions of therapeutic research include the treatment of patients with low stage disease, more precise identification of patients requiring therapy, and more precise definition of therapeutic response.