Unrelated Cord Blood Transplantation for Acute Leukemia Diagnosed in the First Year of Life: Outcomes and Risk Factor Analysis

Infant acute leukemia still has a poor prognosis, and allogeneic hematopoietic stem cell transplantation is indicated in selected patients. Umbilical cord blood (UCB) is an attractive cell source for this population because of the low risk of chronic graft-versus-host disease (GVHD), the strong graft-versus-leukemia effect, and prompt donor availability. This retrospective, registry-based study reported UCB transplantation (UCBT) outcomes in 252 children with acute lymphoblastic leukemia (ALL; n = 157) or acute myelogenous leukemia (AML; n = 95) diagnosed before 1 year of age who received a single-unit UCBT after myeloablative conditioning between 1996 and 2012 in European Society for Blood and Marrow Transplantation centers. Median age at UCBT was 1.1 years, and median follow-up was 42 months. Most patients (57%) received a graft with 1 HLA disparity and were transplanted in first complete remission (CR; 55%). Cumulative incidence function (CIF) of day 100 acute GVHD (grades II to IV) was 40% ± 3% and of 4-year chronic GVHD was 13% ± 2%. CIF of 1-year transplant-related mortality was 23% ± 3% and of 4-year relapse was 27% ± 3%. Leukemia-free-survival (LFS) at 4 years was 50% ± 3%; it was 40% and 66% for those transplanted for ALL and AML, respectively (P = .001). LFS was better for patients transplanted in first CR, regardless of diagnosis. In multivariate model, diagnosis of ALL (P = .001), advanced disease status at UCBT (<.001), age at diagnosis younger than 3 months (P = .012), and date of transplant before 2004 were independently associated with worse LFS. UCBT is a suitable option for patients diagnosed with infant acute leukemia who achieve CR. In this cohort, patients with AML had better survival than those with ALL.