At ASBrS 2025, experts showcased how MRD testing in breast cancer is revolutionizing patient care. Using Natera’s Signatera, clinicians detect circulating tumor DNA (ctDNA) to identify recurrence risks early. This post dives into the key takeaways, exploring MRD testing’s role in neoadjuvant, adjuvant, and surveillance settings.
What Is MRD Testing in Breast Cancer?
MRD testing identifies cancer DNA in the blood post-treatment. Unlike imaging, which may miss early signs, Signatera’s tumor-informed approach offers unmatched sensitivity. By sequencing tumor-specific mutations, it pinpoints patients needing escalated therapy or those who can avoid overtreatment.
Up to 30% of breast cancer patients face recurrence. MRD testing enables early intervention, potentially boosting survival. It also reduces unnecessary treatments, improving quality of life and cutting costs.
How Signatera Works
Signatera sequences a patient’s tumor and germline DNA to create a personalized test. Initial sequencing takes four weeks, with follow-up tests delivering results in one week. This speed supports timely, data-driven decisions.
Applications in Breast Cancer Management
ASBrS 2025 highlighted three core applications of MRD testing in breast cancer:
- Neoadjuvant Setting: Evaluates treatment response early, guiding therapy adjustments in triple-negative breast cancer.
- Surveillance: Detects recurrence before symptoms, prompting imaging for earlier action.
- Therapy Optimization: Identifies patients who benefit from therapies like CDK4/6 inhibitors, minimizing side effects.
Real-World Examples
Dr. Erica Giblin shared cases where Signatera transformed care. One patient, non-compliant with therapy, tested positive, leading to a treatment switch and a negative result. Another case caught asymptomatic bone metastases, enabling early intervention. These examples show MRD testing’s power to personalize care.
Challenges and Future Potential
Despite its promise, MRD testing faces hurdles. Insurance coverage varies, though most patients pay little out-of-pocket. False positives are rare (<1%), but false negatives can occur with low-burden tumors. Trials like ERTC Treat ctDNA are exploring whether early intervention improves survival.
Upcoming ASCO and ESMO presentations will explore MRD testing’s role in surgical planning and predicting nodal burden, signaling a bright future.
Why MRD Testing Matters
MRD testing in breast cancer meets critical needs: identifying high-risk patients, sparing low-risk ones, and enhancing outcomes. Dr. Angel Rodriguez emphasized, “We shouldn’t do more unless we’re improving survival.” Signatera empowers clinicians to act with precision.
Patients value the insights. Over 90% appreciate MRD testing’s role in decision-making, with minimal anxiety when guided properly.
Explore MRD Testing
Interested in MRD testing? Visit Natera’s Signatera page or explore hereditary cancer testing. For more on breast cancer surveillance, see ASCO’s guidelines.
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