Salvage chemotherapy followed by granulocyte colony‐stimulating factor‐primed donor leukocyte infusion with graft‐vs.‐host disease control for minimal residual disease in acute leukemia/myelodysplastic syndrome after allogeneic hematopoietic stem cell transplantation: prognostic factors and clinical outcomes

This study investigated the prognostic factors and clinical outcomes of preemptive chemotherapy followed by granulocyte colony‐stimulating factor‐primed donor leukocyte infusion (Chemo‐ DLI ) according to minimal residual disease ( MRD ) status in patients with acute leukemia and myelodysplastic syndromes who received allogeneic hematopoietic stem cell transplantation ( HSCT ) ( n  =   101). Patients received immunosuppressive drugs to prevent graft‐vs.‐host disease ( GVHD ) after Chemo‐ DLI . The 3‐yr cumulative incidences of relapse, non‐relapse mortality, and disease‐free survival ( DFS ) after HSCT were 39.5%, 9.6%, and 51.7%, respectively. The cumulative incidences of relapse and DFS were significantly poorer in patients who exhibited early‐onset MRD . Forty‐four patients turned MRD negative 1 month after Chemo‐ DLI ; their cumulative incidences of relapse and DFS were significantly better than those with persistent MRD 1 month after preemptive Chemo‐ DLI (relapse: 19.8% vs. 46.8%, P =  0.001; DFS : 69.6% vs. 46.4%, P =  0.004). The cumulative incidences of relapse and DFS after HSCT were significantly better in patients with chronic GVHD ( cGVHD ) than those without cGVHD (relapse: 19.6% vs. 63.7%, P  <   0.001; DFS : 74.4% vs. 23.8%, P <  0.001). Early‐onset MRD , persistent MRD after Chemo‐ DLI , and non‐ cGVHD after Chemo‐ DLI , which were associated with increased relapse and impaired DFS , suggest unsatisfactory response to preemptive Chemo‐DLI.