Real-world eligibility for adjuvant CDK4/6 therapy in HR+/HER2− early breast cancer: A comparative analysis of monarchE and NATALEE criteria from a single-institution cohort.

e12532 Background: Adjuvant CDK4/6 inhibitors benefit selected HR+/HER2− early breast cancer (EBC), yet monarchE (high-risk node-positive) and NATALEE (broader stage II–III, including high-risk N0) define eligibility differently. Real-world applicability across treatment settings is unclear. Methods: Retrospective study of consecutive stage I–III HR+/HER2−/low EBC treated at KFMC (Jan-2021–Dec-2023). Exclusions: HER2-positive, TNBC, metastatic at diagnosis, or missing key variables. For neoadjuv