Prophylactic Donor Lymphocyte Infusion Based On Two Different Time For Preventing Relapse In Advanced Acute Leukemia Undergoing Allo-Hsct: Comparison Of Two Independent Prospective Cohorts

Background: Prophylactic donor lymphocyte infusion (pDLI) can reduce relapse in advanced acute leukemia (AL) undergoing allogeneic hematopoitic stem cell transplantation (allo-HSCT), but the optimal timing of pDLI remains uncertain. Our previous study demonstrated that pDLI on day +60 post-transplant regardless of minimal residual disease (MRD) could reduce relapse, but the incidence and mortality of graft-versus-host disease (GVHD) were high. To reduce GVHD post-pDLI, we modified our pDLI strategy by delaying the time to day +90 unless MRD was positive on day +60.