Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 12 3 2018 07 04 184 190 EN Mohammad Vaezi Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Mohammad Zokaasadi Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Shervin Shahsavari Pour Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Amir Kasaeian Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Mohsen Nikbakht Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Hosein Kamranzdeh Fumani Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Kamran Alimoghaddam Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran Ardeshir Ghavamzadeh Hematology, Oncology and Stem Cell Transplantation Research Center, Tehran University of Medical Sciences, Tehran, Iran 2017 11 25 2018 02 14 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. https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/880 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/880/639