The induction course was MAE or IAE. Risk-stratified therapy and dose-dense intensive chemotherapy were adopted in the consolidation therapy. After the second course of therapy, patients in remission were stratified into three risk groups: low-risk children were defined as those with t(8;21) and a WBC lower than 50,000/L, inv(16), or an age younger than 2 years without any high-risk factors; high-risk children were those with CR after consolidation course 1 or induction C , or with abnormalities of monosomy 7, 5q-, t(16;21), t(9;22)(Philadelphia chromosome [Ph1]); intermediate-risk children were those who were not in either a low-risk or high-risk group. HSCT was indicated for only relapsed patients in the second CR.
Dose-dense intensive chemotherapy and high dose of Ara-C in the consolidation therapy.