Endocrine Sensitivity and the Prognostic and Clinical Implications

Video content above is prompted by the following:

• What proportion of patients with HR+/HER2– breast cancer experience resistance to first-line endocrine therapy plus CDK4/6 inhibitor?
• What are some of the mechanisms of resistance that can emerge following endocrine therapy and CDK4/6 inhibitors in HR+/HER2– breast cancer?
• How you think about endocrine resistance in the post-CDK4/6 setting? What signals—clinical, molecular, or otherwise—influence your treatment sequencing decisions?
• How does treatment resistance after first-line treatment create challenges in selecting second-line therapies?