The Role of Donor Leukocyte Infusions in the Treatment of Relapsed Acute Leukemia after Allogeneic Stem Cell Transplantation: A Retrospective Analysis

Background: allogeneic hematopoietic stem cell transplantation (allo-hsct) is the only treatment offered for acute leukemias with potential curative capability. one of the main reasons of treatment failure in patients after allo-hsct is return of the primary disease. this study aimed to evaluate the role of different modalities available to treat the patients with relapsed acute leukemia after allo-hsct, focusing mainly on donor leukocyte infusions (dlis).materials and methods: this study included 277 patients who relapsed after myeloablative allo-hsct between february 2003 and february 2015. treatment option was offered to all patients, but it was not accepted by about one-third of the study participants. treated patients were categorized based on receipt of dli (dli-based vs. non dli-based). the effect of treatment in all patients and then the effect of dli among the treated group was evaluated. kaplan-meier method was used for calculating survival rates. all patients were relapsed cases, thus only overall survival (os) was calculated.results: one hundred and forty-five all patients and 132 aml patients were included in the study. one year survival rate for treated patients was 25.13% and for patients who received best supportive care was 2.79% (p<0.001). the difference was significant in both aml and all groups. using dli-based treatments were accompanied by a noticeably superior outcome. hazard ratio was 0.43 (0.29-0.63) for dli-based treatments (p<0.001).conclusion: despite the poor prognosis of relapsed acute leukemia after hsct, it seems that treatment interventions and, especially dli-based treatments, can be of substantial benefit for patients.