Hematopoietic stem cell transplantation in children and adolescents with nonremission acute lymphoblastic leukemia

Background The appropriateness of allogeneic hematopoietic stem cell transplantation (HSCT) in children and adolescents with leukemia in whom complete remission is not possible remains unclear. This retrospective analysis aimed to investigate the outcomes associated with HSCT, and the risks of HSCT in children and adolescents with nonremission acute lymphoblastic leukemia (ALL). Procedure Data from the Japan Society for Hematopoietic Cell Transplantation registry on 325 patients with nonremission ALL (aged 25% bone marrow blasts, T‐cell phenotype, poor‐risk or normal cytogenetics, and history of HSCT were predictors of a poor outcome. Patients scoring 0‐1 (n = 109), 2 (n = 91), and 3‐7 (n = 125) had a 3‐year overall survival of 41% (95% CI: 31‐51%), 21% (95% CI: 13‐31%), and 7% (95% CI: 3‐12%), respectively. Conclusion These results support HSCT in certain nonremission patients. Even in patients without complete remission, outcomes differed according to pre‐HSCT factors. A scoring system could help determine the appropriateness of HSCT in children and adolescents with nonremission ALL.