The FDA has awarded breakthrough device designation to Quest Diagnostics’ Haystack MRD test, a highly sensitive ctDNA assay designed for patients with stage II colorectal cancer after surgery. The test could reshape how clinicians identify who truly benefits from adjuvant therapy — a decision that has long been clouded by uncertainty.
Key Takeaways
1. A major step in early detection
- MRD (minimal residual disease) often evades standard tools like imaging and CEA testing.
- Haystack uses ultrasensitive next-gen sequencing to detect tiny fragments of ctDNA months before recurrence is visible on scans.
2. Personalized precision
- The test is tumor-informed: it first learns a patient’s unique tumor “fingerprint” (up to 70 variants), then tracks these in blood samples with high specificity.
- This individualized approach could transform post-surgical monitoring.
3. Backed by clinical evidence
- Data from the DYNAMIC trial showed ctDNA-guided therapy decisions were as effective as standard care for 3-year recurrence-free survival — while cutting down unnecessary chemotherapy.
- This makes ctDNA-guided monitoring especially valuable for low-risk stage II patients.
4. Beyond colorectal cancer
- Quest plans to validate Haystack across other solid tumors, including its role in treatment response, recurrence monitoring, and pharma clinical trials.
5. Why it matters
- For oncology, this is more than a test — it’s a paradigm shift.
- Earlier, more accurate detection of recurrence means clinicians can tailor therapy, avoid overtreatment, and improve survival outcomes.