The Role of CDK4/6 Inhibitors in ER-Positive, HER2-Negative Metastatic Breast Cancer

In this segment, Dr. Gregory Vidal explains why CDK4/6 inhibitors are commonly added to endocrine therapy in the treatment of ER-positive, HER2-negative metastatic breast cancer. He describes how CDK4/6 inhibitors work by targeting proteins involved in cell cycle progression, specifically blocking signals that allow cancer cells to divide and multiply. When combined with endocrine therapy, which blocks estrogen signaling, CDK4/6 inhibitors provide a complementary mechanism that enhances tumor control. Dr. Vidal emphasizes that this combination approach has become a standard first-line strategy because it has been shown to improve progression-free survival compared with endocrine therapy alone. He also discusses the importance of balancing efficacy with side effect management and highlights that treatment decisions remain individualized. This segment helps patients understand how combining therapies can more effectively control ER-positive, HER2-negative metastatic breast cancer by targeting multiple pathways involved in tumor growth.