Allogeneic hematopoietic cell transplantation for adults with acute myeloid leukemia conducted in Japan during the past quarter century.

Acute myeloid leukemia (AML) represents the most common indication for allogeneic hematopoietic cell transplantation (HCT). This study aimed to address the implementation status of allogeneic HCT for adults with AML in Japan and to provide a comprehensive overview of post-transplant outcomes. For this purpose, we analyzed data of 15,186 patients undergoing allogeneic HCT between 1992 and 2016 who were consecutively reported to the Japanese nationwide transplantation registry. The constant increase in the annual number of transplantations was clearly attributable to the growth of unrelated transplantation, and umbilical cord blood transplantation currently accounts for one-third of all allogeneic HCTs. The proportion of older patients has increased steadily since 2000, approximately, in parallel with the introduction of reduced-intensity conditioning. The probability of overall survival (OS) was estimated at 41% (95% confidence interval (CI), 40-42%) for the entire cohort, 56% (95% CI, 55-57%) for patients transplanted in complete remission (CR), and 22% (95% CI, 21-23%) for those transplanted in non-CR. Multivariate analysis identified age, sex, performance status, disease status, cytogenetic risk, donor type, graft source, sex mismatch between the donor and the recipient, and year of transplantation as factors significantly associated with OS. These findings represent the real-world data in Japan, showing the changes in transplantation practice and a detailed estimation of post-transplant outcomes.