Validation of the European Group for Blood and Marrow Transplantation (EBMT) Risk Score in Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation at a Single Center in Japan

We validated the European Group for Blood and Marrow Transplantation (EBMT) risk score in 273 consecutive adult patients receiving allogeneic hematopoietic stem cell transplantation between 2000 and 2010 at our center. The patients were divided into four groups according to the EBMT risk score: low risk (LR, score 0-2), intermediate risk-1 (IR-1, score 3), intermediate risk-2 (IR-2, score 4), and high risk (HR, score 5-7). The five-yr overall survival of the LR (n = 65), IR-1 (n = 67), IR-2 (n = 70), and HR (n = 71) groups was 72%, 57%, 41%, and 25%, respectively (p < 0.001). The five-yr transplant-related mortality rates were 16%, 30%, 25%, and 36%, respectively (p = 0.07). The five-yr cumulative incidence of relapse was 20%, 18%, 37%, and 41%, respectively (p < 0.001). In the subgroup analysis, the prognostic value of the EBMT risk score was confirmed in patients undergoing myeloablative conditioning (MAC), but not in those undergoing reduced-intensity conditioning (RIC). The results suggest that the EBMT risk score is a useful tool to predict transplant outcome for patients undergoing MAC, but not for those undergoing RIC and may be beneficial for stratifying patients in clinical studies.