Research Progress on CDK4/6 Inhibitors Combined with Endocrine Therapy for Advanced Breast Cancer

The introduction of CDK4/6 inhibitors has revolutionized the treatment paradigm for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer. These inhibitors, when combined with endocrine therapy, have shown significant improvements in both progression-free survival (PFS) and overall survival (OS). However, the development of resistance presents substantial challenges that limit their long-term effectiveness. This article provides a review of the mechanisms of action, clinical efficacy, and safety of CDK4/6 inhibitors, as well as treatment after disease progression on a CDK4/6 inhibitor, offering valuable references.