Evaluation of Trends and Prognosis Over Time in Patients with AML Relapsing After Allogeneic Hematopoietic Cell Transplant Reveals Improved Survival for Young Patients in Recent Years.

Abstract

Relapsed acute myeloid leukemia (AML) post allogeneic hematopoietic cell transplantation (allo-HCT) has a dismal prognosis. To assess prognosis of patients with recurrent AML post allo-HCT over time, we analyzed European Society for Blood and Marrow Transplantation registry data of 8,162 adult patients with AML who relapsed between 2000 and 2018 after allo-HCT performed in first complete remission from matched sibling, unrelated, or haploidentical donors. The 2-year overall survival (OS) rate from relapse was 17%. For 3,630 patients, <50 years of age, the 2-year OS continuously increased from 16% between 2000 and 2004 to 18% for 2005-2009, to 21% for 2010-2014, and to 26% for 2015-2018 (<i>P</i> = 0.001). Improvement over time was noted both after relapse within and beyond 6 months from allo-HCT. On multivariate analysis among patients <50 years of age, OS was positively affected by a later year of relapse (baseline: 2000-2004; HR, 0.82; <i>P</i> < 0.02 for 2010-2014 and HR, 0.72; <i>P</i> = 0.0002 for 2015-2018), good performance status, favorable cytogenetics, and longer time from transplant to relapse, but negatively affected by increasing age. In contrast, among 4,532 patients, >50 years of age, the year of relapse had no influence on OS (16% for 2000-2004 and 14% for 2015-2018; <i>P</i> = 0.56). Regarding treatment, encouraging results were observed after second allo-HCT, which was performed within 2 years after relapse in 17% of the entire cohort, resulting in a 2-year OS of 30.7%. Outcome after posttransplant relapse among younger patients has improved significantly in recent years, likely reflecting, among other factors, the efficacy of posttransplant salvage including second allo-HCT.