A comparative study of unrelated donor and matched-sibling donor allogeneic hematopoietic stem cell transplantation in children and adolescents with acquired severe aplastic anemia

Abstract

Objective: To evaluate the efficacy of unrelated donor allogeneic hematopoietic stem cell transplantation(URD allo-HSCT) for children and adolescents with severe aplastic anemia (SAA). Methods: Clinical data of 34 SAA children and adolescents undergoing allo-HSCT were retrospectively analyzed from October 2001 to October 2015. According to the source of donor, the patients were divided into matched sibling donor allo-HSCT group (MSD group) and unrelated donor group (URD group). The clinical outcome of SAA children and adolescents receiving URD allo-HSCT was assessed, and patients in MSD allo-HSCT group were enrolled as control at the same period. Results: The rate of hematopoietic reconstitution, the time of neutrophil and platelet engraftment, incidence of chimerism and graft rejection between two groups were not statistically different.The incidence of acute graft-versus-host disease (GVHD) in URD group was significantly higher than that in MSD group [42.9%(6/14) vs 10.5%(2/19), P=0.047]. The incidence of grade Ⅱ-Ⅳ acute GVHD and chronic GVHD in URD were higher than those in MSD group [21.4%(3/14) vs 5.3%(1/19), P=0.288; 35.7%(5/14) vs 5.3%(1/19), P=0.062, respectively], yet without significant difference between two groups. Other transplant-related complications including pulmonary complications, hemorrhagic cystitis, incidence of EBV and CMV reactivation and venous occlusive disease were comparable with two regimens. Estimated 5-years overall survival (OS) rate and disease free survival (DFS) rate were not statistically significant between URD group and MSD group [(84.4±6.6)% vs (89.4±7.1)%, (82.5±5.4)% vs (82.1±4.3)%; P=0.766, P=0.884, respectively]. Conclusions: By multivariate analysis, the outcome of URD allo-HSCT in SAA children and adolescent is similar to MSD allo-HSCT. It could be an alternative option as the first-line treatment for SAA children and adolescents without HLA matched sibling donors.