Comparable Outcomes for Hematologic Malignancies after HLA-Haploidentical Transplantation with Posttransplantation Cyclophosphamide and HLA-Matched Transplantation

The implementation of high-dose posttransplantation cyclophosphamide (PTCy) has made HLA-haploidentical (haplo) blood or marrow transplantation (BMT) a cost effective and safe alternative donor transplantation technique, resulting in its increasing utilization over the last decade. We review the available retrospective comparisons of haplo BMT with PTCy and HLA-matched BMT in adults with hematologic malignancies. The examined studies demonstrate no difference between haplo BMT with PTCy and HLA-matched BMT with regard to acute graft-versus-host disease (aGVHD), nonrelapse mortality, and overall survival. Chronic GVHD occurred less frequently after haplo BMT with PTCy compared with HLA-matched BMT utilizing standard GVHD prophylaxis. In addition, patients with a high risk of relapse by the disease risk index had a suggestion of improved progression-free and overall survival after haplo BMT with PTCy when compared with a historical cohort of HLA-matched BMT in one analysis. Furthermore, in Hodgkin lymphoma relapse and progression-free survival were improved in the haplo BMT with PTCy compared with the HLA-matched BMT cohort. These findings support the use of this transplantation platform when HLA-matched related donors (MRDs) are unavailable and suggest that clinical scenarios exist in which haplo BMT may be preferred to HLA-matched BMT, which warrant further investigation.