Allogeneic bone marrow transplantation in first remission for children with very high-risk acute lymphoblastic leukemia: a retrospective case-control study in the Nordic countries. Nordic Society for Pediatric Hematology and Oncology (NOPHO)

Abstract

Among children with high-risk (HR) ALL there are subgroups with very-high-risk (VHR) features and poor prognosis despite developments in conventional chemotherapy for childhood ALL. We evaluated the outcome of VHR-ALL in children receiving allogeneic BMT (allo-BMT) in first remission (1CR) in a retrospective case-control study. In the population-based ALL material of the five Nordic countries, 22 children with VHR-ALL have undergone allo-BMT in 1CR between 1981-1991. We compared the outcome in these 22 children with 44 closely matched control patients who received conventional chemotherapy on HR-ALL protocols, as well as with a group of 405 children representing the remaining HR-ALL patients in the Nordic ALL database. The disease-free survival at 10 years was 73% in children receiving allo-BMT in 1CR, 50% in the matched controls (P = 0.02), and 59% in the remaining HR-ALL patients. The good prognosis of the allo-BMT group was due to a low relapse rate of 9%, as opposed to 41% in the group of matched controls. The superiority of allo-BMT as therapy in 1CR was mainly apparent in those with a very high WBC of > or = 100 x 10(9)/I at diagnosis; in the allo-BMT group 9/10 survived, as opposed to 8/20 of the matched controls (P = 0.03). We conclude that allo-BMT in 1CR should be seriously considered for children with a matched sibling donor and a VHR-ALL with WBC of > or = 100 and other established VHR criteria.