Intensive timed sequential remission induction chemotherapy with high-dose cytarabine for childhood acute myeloid leukemia

Background. Timed sequential chemotherapy and high-dose cytarabine (cytosine arabinoside, Ara-C; HDAC) are both effective treatments for acute myeloid leukemia (AML). We review our institutional experience with timed sequential induction chemotherapy consisting of daunorubicin/Ara-C/-thioguanine (DAT) or idarubicin/Ara-C/-thioguanine (IAT) followed on day 14 by HDAC regardless of the degree of marrow aplasia for children with newly diagnosed AML. Procedure. Children presenting with newly diagnosed AML were treated with induction chemotherapy consisting of idarubicin (12 mg/m²/day on days 1-3 or daunorubicin at 45 mg/m²/day for the first five patients), Ara-C (100 mg/m²/day by continuous infusion on days 1-7), and thioguanine (100 mg/m²/day on days 1-7). HDAC (1 g/m²/ dose every 12 hr for 10 doses) was administered beginning on day 14, regardless of the results of bone marrow examination. Results. Thirteen children received timed sequential HDAC. Only one child received HDAC later than Day 18. Eleven of the children achieved a complete remission. All patients experienced grade 4 hematologic toxicity, and all had fever as well. There were 11 children with documented infections. Ten had grade 3 or 4 GI toxicity. One patient died of sepsis. Conclusions. HDAC administered as a part of timed sequential therapy yields an excellent remission induction rate with manageable toxicity.