A Potential Paradigm Shift in Testing Strategies in First-Line HR-Positive/HER2-Negative Advanced Breast Cancer: Can We Identify Emerging Endocrine Resistance Earlier?

This content was funded by AstraZeneca.

Discover how recent Phase 3 trials in HR-positive, HER2-negative metastatic breast cancer are exploring a potential shift from the current ESR1 testing strategy to an investigational approach.^1-3 This video explains the role of ESR1 mutations in breast cancer progression,⁴ how they contribute to endocrine resistance,⁴ and how early detection through circulating tumor DNA (ctDNA) monitoring may help identify patients at risk of disease progression sooner.^1,2

Topics covered 

• The role of ESR1 mutations in HR-positive breast cancer progression⁴
• How aromatase inhibitor exposure influences the development of ESR1 mutations⁴
• How the current ESR1 testing strategy compares with an investigational strategy involving early ctDNA monitoring^1-3
• How earlier ESR1 mutation detection could inform treatment decisions and potentially delay endocrine resistance^1,2

References  

1. Bidard FC et al. Lancet Oncol. 2022;23(11):1367-77.
2. Turner N et al. Future Oncol. 2023;19(8):559-73.
3. Burstein HJ et al. J Clin Oncol. 2023;41(18):3423-5.
4. Brett JO et al. Breast Cancer Res. 2021;23(1):85.

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