Second-Line Treatment Considerations in HR+/HER2− mBC

Dr. Seth Wander introduces the program and welcomes Dr. Erica Mayer, Dr. Kathryn Post, and Dr. Jennifer Hutchinson for a multidisciplinary discussion focused on the evolving treatment landscape for hormone receptor-positive, HER2-negative metastatic breast cancer (HR+/HER2− mBC). The panel begins by establishing the clinical significance of first progression after treatment with a CDK4/6 inhibitor plus an aromatase inhibitor and the increasing complexity of second-line treatment selection. Dr. Mayer explains that treatment decisions should incorporate disease characteristics, including disease volume and visceral involvement, patient performance status, prior treatment experience, and individual goals of care. She emphasizes the growing importance of biomarker testing because acquired resistance alterations can provide actionable information for subsequent therapy. The discussion introduces the role of genomic assessment in guiding treatment sequencing and sets the stage for a broader review of current and emerging therapeutic options for patients with HR+/HER2− mBC.