Impact on RFS and OS of FLT3-ITD AR focus on patients younger than 70 years with intermediate prognosis based on karyotype and NPM1 mut. (A) RFS (left) and OS (right) of patients <70 years with intermediate prognosis based on karyotype stratified for FLT3-ITD AR. The low-AR group was found to have significantly better outcomes in both RFS and OS than the high-AR group (RFS at 5 years: low-AR group 51.9% vs high-AR group 22.8%, P = .017; OS at 5 years: low-AR group 41.9% vs high-AR group 17.1%, P = .049). (B) RFS (left) and OS (right) of NPM1 mut–positive cases stratified for FLT3-ITD AR. When analysis was restricted to NPM1 mut–positive cases, RFS and OS were again found to be significantly more favorable in the low-AR group than the high-AR group (RFS at 5 years: low-AR group 50.5% vs high-AR group 11.7%, P = .026; OS at 5 years: low-AR group 41.3% vs high-AR group 14.7%, P = .041). However, in contrast to the classification of the ELN guidelines,²⁵  the low-AR group, with a 5-year survival rate of 41.3%, was found to have not a good but an intermediate prognosis, and the high-AR group, with a 5-year survival rate of 14.7%, was found to have not an intermediate but an unfavorable prognosis.