Evolving Risk Classifications in AML in a Real-Life Scenario: After Changes upon Changes, Is It More and More Adverse?

Comparison of disease and risk classifications of AML before and after incorporation of NGS analysis of bone marrow samples

Mutation profiling by next-generation sequencing (NGS) has facilitated understanding of the molecular pathogenesis of acute myeloid leukemia (AML), and has been incorporated into the new disease classification (International Consensus Classification; ICC) and risk classification (European LeukemiaNet [ELN] 2022; ELN2022). We compared disease subtypes between the previous disease classification (4th edition of the WHO classification; WHO-4) and the ICC in 91 patients with AML diagnosed at our institution. We also compared disease risk classifications using the previous risk classification (ELN2017) and the ELN2022. Targeted sequencing of bone marrow samples was conducted at Kyoto University. We found that entities under AML with recurrent genetic abnormalities were well-established, with almost no change from the WHO-4 to the ICC. In contrast, 16.7% of cases of AML, not otherwise specified in the WHO-4 were reclassified into AML with mutated TP53, and 36.7% were reclassified into AML with myelodysplasia-related gene mutations or cytogenetic abnormalities per the ICC. Meanwhile, the ELN2017 and ELN2022 showed no difference in concordance indexes in multivariate Cox regression analysis for progression-free and overall survival. The superiority of the ELN2022 over the ELN2017 could not be confirmed in our single-center retrospective study, and further investigation including multicenter prospective studies is needed.

Precision Medicine Approaches in Acute Myeloid Leukemia with Adverse Genetics

The treatment of acute myeloid leukemia (AML) with adverse genetics remains unsatisfactory, with very low response rates to standard chemotherapy and shorter durations of remission commonly observed in these patients. The complex biology of AML with adverse genetics is continuously evolving. Herein, we discuss recent advances in the field focusing on the contribution of molecular drivers of leukemia biogenesis and evolution and on the alterations of the immune system that can be exploited with immune-based therapeutic strategies. We focus on the biological rationales for combining targeted therapy and immunotherapy, which are currently being investigated in ongoing trials, and could hopefully ameliorate the poor outcomes of patients affected by AML with adverse genetics.

Assessment of 2022 European LeukemiaNet risk classification system in real-world cohort from China

BACKGROUND

The European LeukemiaNet (ELN) risk classification system for acute myeloid leukemia (AML) patients has been used worldwide. In 2022, the ELN risk classification system modified risk genes including CEBPA mutation status, myelodysplasia-related (MR) gene mutations and internal tandem duplications of FLT3 (FLT3-ITD).

METHODS

We include newly diagnosed de novo AML patients at our center from January 2017 to December 2021, regardless of the further treatment received. Clinical data and date of survival were included. Survival analysis were performed using the Kaplan-Meier method, and the log-rank test was used to compare survival between different risk groups.

RESULTS

We include 363 newly diagnosed de novo AML patients from 2017 to 2021 to assess the accuracy of the ELN risk classification system. Their survival results show that the ELN-2022 risk classification system is not superior to the ELN-2017 version; for patients with FLT3-ITD mutations but without FLT3 inhibitor treatment, their survival is similar to the ELN-2022 adverse risk group. The ELN-2022 risk classification system cannot accurately clarify ECOG performance status (PS) 2-4 patients, especially in the ELN-2022 favorable risk group.

CONCLUSION

The ELN-2022 risk stratification system may not be appropriate for patients unable to receive intensive therapy or FLT3 inhibitor; more real-world data is needed to straify patients with worse ECOG PS and inferior intensive therapy.