Allogeneic stem cell transplantation benefits for patients ≥ 60 years with acute myeloid leukemia and FLT3 internal tandem duplication: a study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation

Intermediate-risk cytogenetic acute myeloid leukemia with an internal tandem duplication of FLT3 (FLT3-ITD) is associated with a high risk of relapse and is now a standard indication for allogeneic stem cell transplantation. Nevertheless, most studies supporting this strategy have been performed in young patients. To address the benefit of allogeneic transplantation in elderly patients, we selected from the EBMT registry de novo intermediate-risk cytogenetic acute myeloid leukemia harboring FLT3-ITD in patients with an age equal or over the age of 60 years and transplanted from a related or unrelated donor between January 2000 and December 2015. Two hundred and ninety-one patients were identified. Most patients received a reduced-intensity conditioning (82%) and donor consisted of an unrelated donor in 161 (55%) patients. Two hundred twelve patients received their transplantation in first remission, 37 in second remission and 42 in more advanced stage of the disease. The 2-year leukemia-free survival was 56% in patients in first remission, 22% in those in second remission and 10% in patients with active disease, respectively (p<0.005). Non-relapse mortality for the entire cohort was 20%. In multivariate analysis, disease status at transplantation was the most powerful predictor of worse leukemia-free survival, graft-versus-host disease and relapse-free survival and overall survival. In this advanced age population, age was not associated with outcome. Based on the current results, allogeneic transplantation translates into a favorable outcome in fit patients ≥ 60 patients with FLT3-ITD acute myeloid leukemia in first remission, similarly to current treatment recommendation in younger patients.