[Molecular Characteristics and Prognostic Analysis of Low-Risk Acute Myeloid Leukemia with Relapse]

To investigate the molecular characteristics of low-risk acute myeloid leukemia (AML) at recurrence, and analyze the factors affecting retreatment efficacy and prognosis.

A retrospective analysis was conducted on the clinical and laboratory data of 31 patients with newly diagnosed low-risk AML who relapsed during consolidation treatment or follow-up after treatment in our hospital from April 2017 to January 2023. Gene mutations before and after relapse were compared, retreatment efficacy following relapse was evaluated, and univariate and multivariate analyses were performed to identify factors influencing treatment efficacy and prognosis.

Gene sequencing results after relapse showed that the most common newly acquired mutation was FLT3-ITD , while RAS mutation detected at initial diagnosis were predisposed to loss of expression during relapse. The median overall survival (OS) after relapse for the entire cohort was 349 (170-528) days, with non-hematopoietic stem cell transplantation (HSCT) group and HSCT group demonstrating median survival times of 210 (106-314) days and not reached, respectively (P =0.001). Multivariate analysis revealed that age ≥60 years was a significant risk factor for achieving remission after retreatment in initially diagnosed low-risk AML patients who experienced relapse (OR =18.222, 95%CI : 1.188-279.597, P =0.037). Additionally, DNMT3A mutation was identified as an independent risk factor for OS (HR=13.165, 95%CI : 2.018-85.877, P =0.007), while HSCT post-relapse demonstrated significant survival benefits (HR=0.133, 95%CI : 0.025-0.698, P =0.017) and served as an independent protective factor for OS.

Relapsed low-risk AML is often associated with loss of RAS and novel mutations in FLT3-ITD . Age ≥60 years and DNMT3A mutations were identified as independent adverse factors for achieving subsequent remission and post-relapse survival, respectively, while HSCT significantly improved patient outcomes.