HR-Positive/HER2-Negative Metastatic Breast Cancer: First-Line Treatment Selection and CDK4/6 Inhibitor Strategies

Dr. Adam Brufsky opens the discussion by introducing the evolving treatment landscape for patients with HR-positive/HER2-negative metastatic breast cancer. Dr. Rita Nanda, Dr. Rebecca Shatsky, and Dr. Virginia Kaklamani discuss the growing importance of biomarker-driven decision-making, including the role of genomic alterations such as ESR1 and PI3K pathway mutations in guiding treatment selection. The panel then explores current approaches to first-line therapy, with a particular focus on selecting among available CDK4/6 inhibitors. Drawing from both clinical trial evidence and real-world experience, the faculty review factors that influence treatment choice, including overall survival data, toxicity profiles, comorbidities, age, frailty, and the presence of central nervous system involvement. The discussion highlights the importance of individualized treatment planning, emphasizing that therapy selection should be guided by the characteristics of the patient and disease rather than a one-size-fits-all approach. The segment also sets the stage for subsequent discussions on triplet regimens and biomarker-guided treatment strategies in metastatic HR-positive/HER2-negative breast cancer.