Second unmanipulated allogeneic transplantation could be used as a salvage option for patients with relapsed acute leukemia post-chemotherapy plus modified donor lymphocyte infusion

Relapse is the main problem after allogeneic hematopoietic stem cell transplantation(allo-HSCT).The outcome of a second allo-HSCT(HSCT2)for relapse post-HSCT has shown promising results in some previous studies.However,little is known about the efficacy of HSCT2 in patients with relapsed/refractory acute leukemia(AL)post-chemotherapy plus modified donor lymphocyte infusion(post-Chemo+m-DLI)after the first allo-HSCT(HSCT1).Therefore,we retrospectively analyzed the efficacy of HSCT2 in 28 patients with relapsed/refractory AL post-Chemo+m-DLI in our center.With a median follow-up of 918(457–1732)days,26 patients(92.9%)achieved complete remission,and 2 patients exhibited persistent disease.The probabilities of overall survival(OS)and disease-free survival(DFS)1 year after HSCT2 were 25.0%and 21.4%,respectively.The cumulative incidences of nonrelapse mortality on day 100 and at 1 year post-HSCT2 were 7.1%±4.9%and 25.0%±8.4%.The cumulative incidences of relapse were 50.0%±9.8%and 53.5%±9.9%at 1 and 2 years post-HSCT2,respectively.Risk stratification prior to HSCT1 and percentage of blasts before HSCT2 were independent risk factors for OS post-HSCT2,and relapse within 6 months post-HSCT1 was an independent risk factor for DFS and relapse post-HSCT2.Our findings suggest that HSCT2 could be a salvage option for patients with relapsed AL post-Chemo+m-DLI.