The Effect of Post-Transplant Cyclophosphamide Administration on Graft-Versus-Host Disease in Allogeneic Bone Marrow Transplantation

<b>Aim</b>: In this study, we aimed to compare patients receiving PTcy with those receiving standard graft-versus-host disease (GVHD) prophylaxis in terms of GVHD development, disease relapse, overall survival, transplant-related mortality, and infection development <b>Methods</b>: Data from 78 patients who underwent allogeneic stem cell transplantation (AHSCT) at Medicana Izmir Hospital between January 2022 and June 2024 were retrospectively evaluated. <b>Results</b>: Myeloablative-related AHSCT was performed on 38 patients (48.7%), myeloablative-unrelated AHSCT was performed on 26 patients (33.3%), and haploidentical AHSCT was performed on 14 patients (17.9%). Acute GVHD was observed in 42 patients (53.8%); it was observed significantly less frequently in the group that received PTcy (<i>p</i> = 0.032) In 15 patients (19.2%), chronic GVHD developed following acute GVHD. It was found that chronic GVHD occurred more frequently in those who did not receive PTcy (<i>p</i> = 0.0001), in sibling transplants (<i>p</i> = 0.037), in those without febrile neutropenia (<i>p</i> = 0.021), and in those with high CMV-DNA levels (<i>p</i> = 0.040). The median OS (months) was found to be 79.16 months. The median OS (months) was higher in patients in the good AML cytogenetic risk group (<i>p</i> < 0.001) and in those who underwent transplantation in first remission (<i>p</i> = 0.021). <b>Conclusions</b>: PTcy significantly reduced the development of acute and chronic GVHD.