In a retrospective analysis of 3,113 patients with acute myeloid leukemia (AML), detectable measurable residual disease (MRD) at the time of allogeneic hematopoietic cell transplantation (allo-HCT) after myeloablative conditioning (MAC) did not significantly affect relapse rates, overall survival, or non-relapse mortality, whereas detectable MRD before reduced-intensity conditioning (RIC) was associated with an increased risk of relapse.

These findings suggest “that MAC may more effectively overcome residual leukemia and limit leukemia relapse, an impact not observed with RIC allo-HCT,” write Daniel J. Weisdorf, MD, of the Clinical and Translational Science Institute at the University of Minnesota and colleagues in a study published online in Leukemia in October. The patients studied were treated between 2008 and 2019 at 450 centers worldwide that reported data to the Center for International Blood and Marrow Transplantation Research.

For MAC recipients, the number of induction/consolidation cycles needed to achieve a complete response (CR) also influenced survival. OS was 1.3–fold better for patients who achieved CR after one MAC cycle than two and 1.47–fold better than three or more. For RIC recipients, the number of induction cycles to CR did not affect OS. However, relapse risk was 1.24– to 1.47–fold greater for patients who received two or more RIC cycles than for those who achieved CR in one cycle.

Among patients treated with allo-HCT after primary induction failure, overall survival was significantly worse than for those who achieved CR. “These data suggest that achieving CR remains a critical goal for all AML patients being considered for allo-HCT, the authors write.

• Boyiadzis M, Zhang MJ, Chen K, et al. Impact of pre-transplant induction and consolidation cycles on AML allogeneic transplant outcomes: a CIBMTR analysis in 3113 AML patients [published online ahead of print, 2022 Oct 30]. Leukemia. 2022;10.1038/s41375-022-01738-3. doi:10.1038/s41375-022-01738-3

Tags: AML, MRD, AlloHCT, BMT, allogeneic transplantation, Relapse, Survival, leukemia, Allo-HCT, bone marrow transplant, allogeneic stem cell transplantation, Allo-HSCT, acute myeloid leukemia, measurable residual disease