Long-term outcomes and GVHD in patients receiving hematopoietic cell transplants abroad: A 14-year UAE multi-center cohort

BackgroundHematopoietic cell transplant (HCT) outcomes are well characterized in clinical trials and international registries, but data remain scarce for patients who undergo transplantation abroad and return home for follow-up. While transplant centers typically report procedural details and early mortality for this cohort, long-term survival and chronic graft versus host disease (GVHD) outcomes are seldom captured, underscoring the need for comprehensive reporting. MethodsWe conducted a retrospective, multi-center study of all HCT recipients followed at all the three tertiary hospitals in Abu Dhabi, UAE, between 2009 and 2023. Patient demographics, transplant characteristics, overall survival (OS), and GVHD incidence were extracted from medical records. Kaplan-Meier OS estimates were calculated for diseases with [&ge;]20 cases; crude survival was reported for rarer indications. ResultsA total of 454 HCTs were analyzed: 350 (77.1%) allogeneic and 104 (22.9%) autologous. Adults undergoing allogeneic HCT were relatively young (median age 35.3 years), reflecting referral practices and the UAEs demographic profile. An unexpected female predominance was observed in pediatric malignancies and immune deficiencies. Matched unrelated donor (MUD) transplants were rare, and the trend remained low over time, underscoring reliance on matched related donor (MRD) and mismatched related donor (MMRD). The incidence of GVHD was high, approaching the upper range of international reports: 69.2% in adults and 45.7% in children. In adults with AML, acute GVHD was associated with an inferior 5-year OS (67.9% vs. 86.2%, p=0.036), whereas chronic GVHD did not significantly impact outcomes. In pediatric AML, both acute and chronic GVHD were linked to poorer survival (<50% at 5 years), while outcomes for B/T-ALL, thalassemia, and SCID exceeded 85-90% at 5 years regardless of GVHD status. ConclusionsHCT outcomes in this transplant tourism cohort were generally comparable to international benchmarks, yet notable for younger adult recipients, predominance of allogeneic over autologous procedures, limited use of MUDs, and a high incidence of GVHD. These observations highlight the urgent need to establish sustainable local transplant capacity, build donor registries, and implement aggressive GVHD prevention and treatment practices to improve outcomes in the UAE.