Performance of the 3-gene regression tree model of EFS in ALL cases. A 3-gene model was developed for prediction of EFS in the entire study cohort. (A) FLT3 expression separates infants into low- versus intermediate- and high-risk disease. Infants with high FLT3 expression are further divided into intermediate- and high-risk disease categories based on IRX2 and TACC2 expression. The ovals and boxes contain the relative risk followed by number of events/number of cases. (B) Kaplan-Meier survival curves show significant differences in EFS among the infants in the low-, intermediate-, and high-risk categories. (C) The model significantly separates MLL-G infants into 2 groups with significantly different EFS. NA indicates HR is not applicable because of absence of failures in 1 group. (D) Validation cohort of 22 MLL-AFF1 cases also is separated into 2 groups with different EFS. No infants with MLL-AFF1 and low FLT3 expression (low risk) were present.