Outcome of hematopoietic stem cell transplantation for pediatric patients with therapy-related acute myeloid leukemia or myelodysplastic syndrome

Abstract

Background. Therapy-related myelodysplastic syndrome (t-MDS) and acute myeloid leukemia (t-AML) carry a poor prognosis. We analyzed the results of allogeneic HSCT in 38 children to determine which factors, if any, affected outcome. Procedure. The effects of demographic, donor, and disease-related factors were analyzed to determine their effects on overall and disease-free survival (OS, DFS), relapse, and non-relapse mortality (NRM). Results. OS and DFS for t-AML and t-MDS were similar. Three-year OS and EFS were the same (15.4 ± 5.8%) and the 3-year NRM was 59.6 ± 8.4%. The 1-year cumulative risk of grade III-IV acute graft-versus-host disease (CVHD) and relapse were 23.7 ± 7.0% and 18.7 ± 6.5%, respectively. The percentage of pre-transplant bone marrow (BM) blasts was positively associated with relapse (P = 0.05), while the percentage of BM blasts at diagnosis of therapy-related disease tended to associate with NRM (P = 0.07). Alternative donor and matched sibling donor grafts had similar outcomes. NRM was higher among patients who did not develop acute CVHD as compared to those with grade 1-2 acute CVHD (69.2 ± 14.2% vs. ± 12.7%, respectively), while NRM was 100% in patients with grade III-IV acute CVHD (P = 0.007). Conclusions. The percentage of BM blasts is associated with relapse in these disorders. High rates of NRM negatively impact the outcome of allogeneic HSCT for children with t-AML and t-MDS. Future studies should focus on reducing NRM. © 2005 Wiley-Liss, Inc.