Endocrine Therapy for Endometrial Carcinoma: Current Evidence, Resistance Mechanisms, and Biomarker-Driven Patient Selection

The treatment landscape for endometrial carcinoma (EC) is undergoing a paradigm shift from traditional histopathological dualism to precision medicine grounded in the Cancer Genome Atlas (TCGA) molecular classification. The "No Specific Molecular Profile" (NSMP) subgroup, the largest molecular cohort, has emerged as a particularly promising target for endocrine-based strategies. While endocrine therapy (ET) has been a mainstay for over 60 years due to its favorable safety profile, its efficacy as monotherapy remains modest. This review provides a comprehensive overview of current endocrine strategies, including traditional agents like progestins and aromatase inhibitors, and focuses on novel combination therapies designed to overcome resistance. Recent clinical trials have demonstrated that integrating molecularly targeted agents, such as CDK4/6 and mTOR inhibitors, significantly improves clinical outcomes. Specifically, patients with <i>TP53</i> wild-type status and <i>CTNNB1</i> mutations exhibit exceptional responses to these combinations. Furthermore, we discuss the potential of next-generation selective estrogen receptor degraders (SERDs) and the importance of refining patient selection through robust predictive biomarkers. Driven by molecular insights, endocrine therapy is transitioning from a secondary palliative option into a definitive cornerstone of precision oncology, offering a personalized and effective treatment for patients with advanced or recurrent endometrial carcinoma.