Chronic lymphoproliferative disorders: chronic lymphocytic leukemia and hairy-cell leukemia.

A consistent stimulus to increase interest in malignant disease is the discovery of new successful treatments. The dramatic activity of the nucleoside analogues, 2'-deoxycoformycin, fludarabine, and 2-chlorodeoxyadenosine, in indolent lymphoproliferative diseases has caused a reawakening of interest in the biology and treatment of chronic lymphocytic leukemia and hairy-cell leukemia. The high response rate has led to a reevaluation of criteria for response in these diseases as well as indications for treatment and prognostic factors.