ABSTRACT
Objective To analyze the safety of high dose methotrexate (HD-MTX) in the treatment of children with acute lymphoblastic leukemia (ALL) after 36 hours and 42 hours using leucovorin (CF) rescue. Methods A total of 137 childhood with acute lymploblastic leukemia(ALL) in our hospital from September 2012 to December 2015 were analysed in this study, 137 children with ALL were randomly divided into group A (n=69) and group B (n=68) according to the serial number (odd number and odd number). The total number of treatment times was 454 times. Among them, the rescue time of group A was 36 hours, there were 224 cases, and the rescue time of group B was 42 hours, 230 times.The plasma drug concentration, delayed excretion rate, the total dose of leucovorin, the total dose of methotrexate and the incidence of side effects were observed in group A and group B at 24, 48 and 96 hours. Results There was no significant difference in plasma concentration, delay of excretion and incidence of side effects between 2 groups of methotrexate, 24, 48 and 96 hours. The total dose of methotrexate/methotrexate in 2 groups was statistically significant (P＜0.05). Conclusion When the rescue time of leucovorin was 42h, the treatment of acute lymphoblastic leukemia with high-dose methotrexate was the best.