Effect of Stem Cell Source and Dose on Allogeneic Hematopoietic Stem Cell Transplantation in Adult Patients with Idiopathic Aplastic Anemia: Data from the Korean Aplastic Anemia Trials

Objective: We aimed to evaluate the effect of stem cell source and dose on the survival of various donor subgroups, such as matched sibling donor (MSDs) and alternative donors (ADs), upon bone marrow (BM) or peripheral blood stem cell (PBSC) infusion in aplastic anemia (AA). Methods: We retrospectively investigated the effects of stem cell source and dose on allogeneic hematopoietic stem cell transplantation (alloHSCT) in AA. Results: A total of 267 patients were included in this analysis. The BM-treated group showed an association with low incidence of any-grade acute graft versus host disease (GvHD) (p < 0.001). A higher stem cell dose was related with a low incidence of extensive chronic GvHD in MSDs (p = 0.025). Multivariate analysis for overall survival (OS) revealed that only age at alloHSCT p = 0.010) and prior platelet transfusion p = 0.046) in MSDs and higher stem cell dose (hazard ratio = 2.596, p = 0.045) in ADs were favorable prognostic factors. Conclusion: PBSCs could be preferred in AD because high stem cell dose may be easily achieved to improve the OS at the expense of acute GvHD. However, BM stem cells are preferred in MSDs.