Kaplan-Meier estimates of survival after HSCT in the HLH-2004 study. Five-year probabilities of survival (pSu) are indicated with a 95% CI. OS or EFS is displayed, where death, and death or second HSCT, were defined as events, respectively. P values from Cox proportional hazards models. (A) OS for the entire HLH-2004 cohort (n = 187, events n = 67). (B) EFS for the entire HLH-2004 cohort (n = 187, events n = 78). (C) OS for children with verified FHL (n = 134, events n = 43, blue line) and children without verified FHL (n = 53, events n = 24, red line dashed); P = .040. (D) EFS for children with verified FHL (n = 134, events n = 54, blue line) and children without verified FHL (n = 53, events n = 24, red line, dashed); P = .27.