Remission induction in children with acute non-lymphocytic leukemia using cytosine arabinoside and doxorubicin or daunorubicin: a report from the Childrens Cancer Study Group.

Four hundred ninety evaluable patients were treated on an induction regimen consisting of two to four courses of cytosine arabinoside plus an anthracycline. Overall, 78% of patients went into remission, 10% died during induction, and 12% were induction failures. For the first 152 patients, courses consisted of 7 days continuous infusion with cytosine arabinoside (Ara-C, 100 mg/m2) and 3 days of doxorubicin (30 mg/m2). Because of unacceptable toxicity, particularly for children less than 3 years of age, the anthracycline was changed to daunorubicin, and the doses of both induction drugs for children under 3 was reduced. For children aged 3 years and older the change in anthracycline was associated with a significant increase in induction failures (7% to 16%, P = .04) and a decrease in deaths (15% to 8%, P = .09). For younger children, for whom doses were also changed, the effect was greater; Mortality decreased from 29% to 1% (P less than .0001), and the remission induction rate increased from 66% to 88% (P = .005). The therapy modifications also influenced survival following remission induction: Daunorubicin-treated patients, aged 3 years and over, did significantly better than those given doxorubicin (P = .03), but the opposite was seen in younger children (P = .06). Gastrointestinal and skin toxicities and septicemia were significantly more common when doxorubicin was being used, but the extent of myelosuppression was similar for the two anthracyclines.