2.5 Definitions and endpoints
Neutrophil engraftment was defined as an absolute neutrophil count of 0.5 ×109/L or more for 3 consecutive days. Platelet engraftment was defined as a platelet count of 20× 109/L or more for 7 consecutive days without transfusion. Acute and chronic GVHD were diagnosed and graded according to established criteria. Risk stratification was differentiated into two groups: AML and ALL in first or second remission (CR1 or CR2), chronic myeloid leukemia (CML) in the first or second chronic phase (CP1 or CP2), and MDS with refractory anemia with or without ringed sideroblasts were defined as the standard-risk group, and other malignant diseases were defined as the high-risk group. Overall survival (OS) times were measured from the date of HSCT until death from any cause. Leukemia-free survival (LFS) was defined as the time from transplantation to relapse or death from any cause. Surviving patients were censored on the date of their last follow-up. Transplantation-related mortality (TRM) was defined as death after allo-HSCT without disease progression or relapse. Relapse was defined by the appearance of morphological evidence of the disease obtained from testing samples from the peripheral blood, bone marrow, or extramedullary sites or by recurrence and the sustained presence of pretransplantation chromosomal abnormalities.