Superior transplantation outcomes of 8/8-matched unrelated donors as well as matched siblings to autologous transplantation for acute myeloid leukemia with intermediate cytogenetics in first remission

Objectives For patients with acute myeloid leukemia in first complete remission (AML CR1) lacking HLA-matched sibling donors (MSD), 8/8-matched unrelated donors (URD) are mostly used in cases with poor-risk features. For AML CR1 with intermediate cytogenetics, however, the benefit of 8/8-matched URD should be compared with non-allogeneic therapies as well as MSD. Methods To address this issue, we assessed the transplantation outcomes of 8/8-matched URD (n = 54) compared with MSD (n = 145) or autologous transplantation (n = 89) for AML CR1 with intermediate cytogenetics. Results In multivariate analyses, 8/8-matched URD had comparable 6-yr overall survival (OS, P = 0.997), disease-free survival (DFS, P = 0.951), and relapse (P = 0.672) to MSD, whereas 8/8-matched URD had a higher OS (P = 0.070) and DFS (P = 0.035) with lower relapse (P = 0.009) than autologous transplantation. No difference in non-relapse mortality was observed according to donor type. Notably, these equivalent or superior outcomes of 8/8-matched URD compared with MSD or autologous transplantation, respectively, were particularly evident in patients without poor-risk features (n = 200), such as older age, hyperleukocytosis at diagnosis, and myelodysplasia-related changes, who are not usual candidates for URD transplantation. Conclusions These results indicate that 8/8-matched URD are feasible next option in AML CR1 with intermediate cytogenetics, when lacking MSD, even in patients without poor-risk features.