Impact of high-dose cytarabine and asparaginase intensification on childhood acute myeloid leukemia: a report from the Childrens Cancer Group.

Abstract

PURPOSE The purpose of this review was to determine the impact of high-dose cytarabine and asparaginase intensification, administered shortly after remission induction, on the outcome of childhood acute myeloid leukemia (AML). MATERIALS AND METHODS Three consecutive Childrens Cancer Group (CCG) trials of acute myeloid leukemia, CCG 251 (1979 to 1983), CCG 213P (1983 to 1985), and CCG 213 (1985 to 1989) with a total of 1,294 patients, were reviewed and provide the basis of this report. RESULTS CCG 213P demonstrated the importance of dose interval, in that two courses of cytarabine and asparaginase administered at 7-day intervals gave superior 5-year survival rates (58% v 41% from the end of induction, P < .04) to the same therapy administered at 28-day intervals. CCG 213 showed that there was no advantage to the maintenance therapy used for patients who received two courses of cytarabine and asparaginase at 7-day intervals (5-year survival, 68% [no maintenance] v 44% [maintenance] from the end of consolidation, P < .01). Inclusion of the 7-day interval cytarabine/asparaginase intensification was accompanied by an overall improvement in 5-year survival rates from diagnosis when compared with historical controls (CCG 213, 36% v CCG 251, 29%, P < .02) although other differences between these studies could also be responsible for the improvement seen. CONCLUSION High-dose cytarabine and asparaginase intensification eliminated the benefit of prolonged maintenance therapy in childhood AML and was accompanied by an overall improvement in survival.