The Efficacy and Safety of Super High-Dose Cytarabine Based Strategies in Childhood Acute Myeloid Leukemia Treatment

Objective The aim of this study was to evaluate the effect of super high-dose cytarabine (SHDAC), a regimen first created by the author, on the five-year overall survival (OS) and event-free survival (EFS) of children with AML. Methods From July 2001 to April 2016, a total of 25 pediatric patients with newly diagnosed AML (exclueding secondary AML、APL and Down Syndrome AML) were enrolled. Patients received consolidate chemotherapy with the same regimen of high-dose cytarabine (3g/m2 every 12 hours by continuous infusion for 6 days) after remission induction chemotherapy. Then phase II consolidation therapy (also known as early intensive treatment) was performed according to the regimen of high-dose cytarabine (3g/m2 every 12 hours on days 1, 3, and 5 for four cycles, a total of 108g/m2) in 16 cases, while the other 9 cases received the treatment with another regimen (H3A7, M3A7 and VP16 combined with cytarabine alternately at intervals ranging from 2 to 6 months). The total treatment course spanned about three years, with regular post-treatment follow-up tracking for more than five years. Results Originally 26 cases were enrolled, but 1 case was not relieved after two courses of treatment and quitted therapy, so only 25 cases were enrolled finally. The total remission rate was 96%. There were 12 cases (48%) achieving complete remission within one course, 12 cases (48%) within two consecutive remission course and one case (48%) ,only one case(4%) achieving complete remission within with in five courses. The five-year OS and EFS of these 25 AML patients in this study were 77±0.98% and 77±1.22% respectively. Four patients (16%) died (1 treatment-related (4%), 3 relapse (12%) including 3 marrow relapse and 1 combined with testicular relapse). The average relapse time was 29.6 months and the median time was 14.8 months. Conclusion The application of super high-dose cytarabine (a total of 108g/m² cytarabine, with a regimen of 3g/m² every 12 hours by continuous infusion for 6 days as consolidation chemotherapy and 3g/m² every 12 hours on days 1, 3, and 5 for four cycles as the early intensive treatment) is clinically safe and effective, with minimal hospitalization expense index (HEI). For patients with financial difficulties, especially those in developing countries, super high-dose cytarabine shows landslide advantages and practicality. Therefore, there should be more collaborative clinical applications as well as research upon related mechanisms.