comparison of cyclophosphamide-based graft versus host disease prophylaxis after allogeneic stem cell transplantation from 9/10 hla matched unrelated donor with standard graft versus host disease prophylaxis after 10/10 hla matched relative donor tr

Background: graft versus host disease (gvhd), which can be observed at a rate of 30-80% after allogeneic stem cell transplantation (asct) is an important complication that adversely affects the survival and quality of the life of patients. posttransplant cyclophosphamide (ptcy) effectively prevents gvhd after hla-haploidentical asct. in our study, the use of ptcy in 1-antigen hla-mismatched unrelated donor (9/10mmud) asct was compared with standard gvhd prophylaxis in hla-identical related donor (mrd) asct.materials and methods: we conducted a retrospective study of the comparison of 42 patients with 9/10 mmud asct receiving ptcy+methotrexate (mtx)+calcineurin inhibitor (cni) and 37 patients with hla-identical mrd who received mtx+cni  in 3 bone marrow transplantation centers. results: cumulative incidences of grade i-ii (64.6% vs 45.4%, p=0.187) or grade iii to iv acute gvhd (35.4% vs54.6%, p=0.187) and chronic gvhd (11.9% vs 29.7%, p=0.096) were similar in the ptcy group and control group. no statistically significant differences were observed between ptcy and the control group in overall survival rate (52.4% vs 62.2%, p=0.381), progression-free survival (1483.97 vs 1200.70 days, p=0.502), relapsed-related mortality rate (21.4% vs 16.2%, p=0.556) and treatment-related mortality rate (16.7% vs 21.6%, p=0.575).conclusion: with the addition of ptcy to standard gvhd prophylaxis in 9/10mmud asct, the risk of gvhd due to incompatibility and unrelated transplantation is eliminated, and transplantation success is achieved with mrd asct. ptcy-based prophylaxis is an effective and safe strategy to prevent gvhd in 9/10 mmud asct without increasing the risk of relapse and treatment-related mortality.