Induction therapy and intensive consolidation with daunorubicin, cytosine arabinoside, and 6-thioguanine in adult acute nonlymphoblastic leukemia.

Twenty-one patients with acute nonlymphocytic leukemia were treated with a regimen including daunorubicin, cytosine arabinoside, and 6-thioguanine and 15 patients (71%) achieved a complete remission. Thirteen of the 15 remissions occurred after a single course of therapy and two after two courses of treatment resulting in a rapid time to complete remission. The time from treatment initiation to complete remission was 21-82 days with a median of 29 days. Nine of the 15 patients who gained a complete remission were then treated with two cycles of consolidation therapy utilizing the three induction drugs in modified dosages to determine the toxicity of a consolidation program. With the doses used in consolidation, pancytopenia regularly occurred but only 5/15 courses were associated with complications of bleeding or infection that required hospitalization. No patient died as a result of consolidation therapy. This study confirms the rapid effectiveness of the induction program which provided equivalent complete remission rates for adults at any age (up to 66 years). The consolidation regimen is now being used in a randomized study to determine whether it contributes to the duration of complete remission.