Utility of allogeneic hematopoietic stem cell transplantation using international donors in a homogenous ethnic population: question in the era of various alternative donors

The advent of various alternative donors in allogeneic hematopoietic stem cell transplantation (HSCT) raises the question of using international donors, especially in ethnically homogenous populations. We analyzed the clinical outcome and medical expense of human leukocyte antigen (HLA)-matched HSCT using domestic and international donors. We analyzed the patients who received allogeneic HSCT at five medical centers in Korea in the last 10years. Using propensity-score matching, we compared overall survival (OS), relapse-free survival (RFS), and transplantation-related complications. Medical expense was analyzed based on National Health Insurance Service (NHIS) data. A total of 269 patients were analyzed after 3:1 (domestic/international) matching. There was no difference in OS (p=0.395) and RFS (p=0.604) between the domestic and international donor groups (5-year OS rate 42.9 and 37.8%, 5-year RFS rate 37.6 and 33.5% for domestic and international groups, respectively). No difference in chronic graft-versus-host disease (GVHD) incidence was observed (34.2% in domestic and 35.9% in international group, p=0.804). Early infection was more frequent in the domestic group (55.0 vs. 35.8%, p=0.007), whereas infection after 30days was more frequent in the international group (28.7 vs. 49.3%, p=0.001). Mean medical expense was far higher in the international group, by US $51,944 in the entire follow-up period (p<0.001). We would expect similar outcomes for international and domestic donors in terms of survival and treatment-related complications with HLA-matched HSCT in other ethnically homogenous populations. These findings should be considered together with the high cost of using international donors in the era of various alternative donors.