Full dose versus attenuated dose daunorubicin, cytosine arabinoside, and 6-thioguanine in the treatment of acute nonlymphocytic leukemia in the elderly.

Between July 1, 1981 and November 1, 1982, 45 patients with acute nonlymphocytic leukemia (age, greater than or equal to 70 years) were randomly assigned to receive induction chemotherapy using either daunorubicin, cytosine arabinoside, and 6-thioguanine in full dosage (F DAT) or an attenuated schedule of the same drugs (At DAT) as part of an Eastern Cooperative Oncology Group controlled trial. Forty patients were deemed evaluable, 20 on each arm. The overall complete remission (CR) rate for all patients in both arms was 28% (11/40). There was no significant difference in CR rates between the two arms. There were 12 early deaths (less than 60 days) in the F DAT arm compared with only five early deaths on the At DAT arm (P = .05). Due primarily to this early death rate, the median survival for the F DAT group was 29 days v 159 days for the At DAT groups (P = .02). The range of survival of the patients in CR for the At DAT group given either one or two cycles of induction therapy was 121 to 414 days, while the survival range for the F DAT CR patients was 121-186 + days. The median survival for those not achieving CR was 14 days for the F DAT group v 80 days for the At DAT (P less than .02). Fifty-nine percent of the At DAT patients spent greater than 100 days out of the hospital v 12% for the F DAT group. Attenuated chemotherapy with lower doses of DAT is the preferred induction regimen for elderly patients with acute nonlymphocytic leukemia since it causes fewer early deaths, allows a better quality of life, and yields survival times as durable as intensive therapy.