Myeloid Neoplasms With Erythroid Predominance and Excess Blasts in Young Adults Exhibit Distinct Genetic Profiles.

The evolution of acute myeloid leukemia (AML) classifications has progressively shifted the diagnostic focus toward genetic criteria. Nevertheless, morphology remains a key element in clinical practice, often serving as the initial trigger for additional molecular investigations. The diagnosis of acute erythroleukemia (AEML), initially defined by the FAB group, is no longer recognized as a distinct entity in the latest WHO and ICC classifications. Some studies have indicated that AEML shares similarities with myelodysplastic neoplasms, including a high frequency of TP53 mutations and adverse karyotypes. Here, we conducted a retrospective analysis in adults with AEML defined using historical morphologic criteria (≥ 50% erythroid precursors and ≥ 20% blasts among non-erythroid cells). In contrast to older patients, young adults (18-60 years) exhibit unique genetic profiles including a high prevalence of normal karyotypes (65%), NPM1 (35%) and UBTF (23%) mutations. AEML morphology in NPM1-mutated cases did not impact clinical outcomes but was associated with specific molecular features, including an enrichment of WT1 and cohesin gene mutations. In this age group, our findings support that morphologically defined AEML often corresponds to AML according to current genetic criteria, consistent with recent classification systems that prioritize molecular features over morphology.