Racial Disparity in Myeloablative Hematopoietic Cell Transplantation Outcomes in Patients with Hematological Malignancies Older Than 45 Years.

Introduction: The impact of race on outcomes of allogeneic hematopoietic cell transplants (HCT) has long been a field of research. The Center for International Blood and Marrow Transplant Research (CIBMTR) studies have shown worse survival for Black and Hispanic patients within the first year after HCT, but rates evened out for one-year survivors. From our personal experience, we hypothesize that the outcomes of South Asians (age ≥ 45 years) receiving myeloablative conditioning (MAC) are also worse compared to other races. Methods: This is a retrospective single-centre study. All patients (age ≥ 45 years) undergoing MAC-HCT for hematological malignancies from 2011-2022 were included. The primary outcome was overall survival (OS). Secondary outcomes were non-relapse mortality (NRM), incidence of grade 2-4 acute graft versus host disease (GVHD), moderate-severe chronic GVHD and relapse incidence (RI). The survival analysis was performed using Kaplan-Meier analysis and log-rank test. The GVHD, NRM and RI rates were calculated using the cumulative incidence (CI) of competing events and the Gray test. EZR was used for statistical analysis. Results: Of the 483 patients included, there were 28 (5.8%) South Asians (SA), 73 (15.1%), other Asians (East Asians (EA)/Southeast Asians (SEA), and 382 (79.1%) Whites (W). Asians were less likely to get matched unrelated donor-HCT than Whites (SA 21%, EA/SEA 30%, W 45%, Conclusion: Our study confirms that South Asians aged ≥ 45 years have worse survival after MAC-HCT. Supportive care is unable to overcome the differences in the outcomes.