Comparison of serum methotrexate concentration and proportion of delayed elimination group at 24 hours. aMethotrexate. *The cycles had plasma MTX concentration at 24hours are 85 cycles, 23 cycles were delayed elimination group. At the 24 hours, the percent of delayed elimination group was compared between MTX concentration greater than 100 μM and less than 100 μM. It was also compared between MTX concentration greater than 150 μM and less than 150 μM