Low incidence of symptomatic osteonecrosis after allogeneic HSCT in children with high‐risk or relapsed ALL – results of the ALL‐SCT 2003 trial

Summary Osteonecrosis (ON) was prospectively assessed in 557 children and adolescents in the Berlin‐Frankfurt‐Münster Stem Cell Transplantation in children with acute lymphoblastic leukaemia 2003 trial. Median age at haematopoietic stem cell transplantation (HSCT) was 10·3 years (range 0·5–26). Cumulative incidence of symptomatic ON (sON) was 9% at 5 years (standard deviation 1%), median time from HSCT to diagnosis of sON was 12·4 months (range 1–126). Multivariate analysis identified age at HSCT [10–15 years vs. 15 years vs.