Differential Diagnosis

Few syndromes can be confused with chronic lymphocytic leukemia. Viral infections producing lymphocytosis should be obvious from the presence of fever and other clinical findings. Other lymphoproliferative diseases such as Waldenstrom’s Waldenström’s macroglobulinemia, hairy cell leukemia, or lymphoma in the leukemic phase are distinguished on the basis of the morphology of circulating lymphocytes and bone marrow.

Treatment

Most cases of early indolent chronic lymphocytic leukemia require no specific therapy. Indications for treatment include progressive fatigue, troublesome lymphadenopathy, or the development of anemia or thrombocytopenia. These patients have either symptomatic and progressive stage II disease or stage III/IV disease. Initial therapy is with chlorambucil, 0.6–1 mg orally every 3 weeks. Complications such as autoimmune hemolytic anemia or immune thrombocytopenia may be treated with high-dose prednisone but often require splenectomy for control. Fludarabine is a new agent which is useful in treating disease refractory to other agents. As initial therapy, fludarabine produces faster and more complete responses than chlorambucil, and the duration of remissions is considerably longer. However, fludarabine causes long-term immunosuppression, and it remains to be determined if it should be used as primary therapy or reserved for use later in the disease. The rare young patient (age under 50) with aggressive disease may be a candidate for allogeneic bone marrow transplantation.

Prognosis

Median survival is approximately 6 years, and 25% of patients live more than 10 years. Patients with stage 0 or I disease have a median survival of 10 years. It is important to reassure these patients that despite the frightening diagnosis of “leukemia” they can live a normal life for many years. Patients with stage III or IV disease have a median survival of less than 2 years. Chronic lymphocytic leukemia is managed in palliative fashion. Patients with advanced disease benefit only briefly from intensive therapy.