Impact of European LeukemiaNet (ELN) guided post-remission therapy on outcome of patients with AML from 2010-2022 Open Access

• The ELN 2017 update resulted in intensified PRT, particularly alloSCT, contributing to significantly improved survival of AML pts.

• Retrospectively reclassifying pts treated from 2017-2022 according to ELN 2010 confirmed improved survival in IR pts without treatment bias.

The European LeukemiaNet (ELN) classification for Acute Myeloid Leukemia (AML) incorporates cytogenetic and mutational risk profiles of AML to define separate risk groups that correlate with survival outcomes. Recommendations for post-remission treatment (PRT) intensity, mainly allogeneic hematopoietic stem cell transplantation (alloSCT), are based on these risk groups. In-depth genetically defined cohorts of registries or clinical trials, often reported as retrospective real-world validation cohorts, contain an inherent bias as patients (pts) were not treated according to recommendations matching time intervals of the respective ELN classification. We analyzed 662 AML pts who received intensive induction therapy at our center between 2010-2022. Pts were classified according to ELN 2010 if treated between 2010-2016, and ELN 2017 if treated between 2017-2022. Overall survival (OS) and relapse-free survival (RFS) significantly improved for pts treated between 2017-2022 compared to 2010-2016 (4-year OS 60% vs. 40%, HR 0.59, p<.0001; 4-year RFS 54% vs. 35%, HR 0.61, p=<.001). To eliminate treatment bias, pts treated between 2017-2022 were retrospectively reclassified for genetic risk according to ELN 2010 and compared to regularly classified pts treated between 2010-2016. The improved outcome was particularly evident for intermediate risk (IR) pts, while favorable and adverse subgroups showed no significant difference. This is the first analysis examining the impact of ELN-guided PRT in the context of treatment algorithms applied in the respective ELN time period. We conclude that the shift of risk groups between ELN 2010 and 2017 with resulting intensified PRT contributed to significantly improved survival of AML pts, particularly in IR pts.