Myriad Expands Precise MRD to 6 Million Cancer Patients, Study Shows 93% ctDNA Detection

Myriad Genetics has broadened availability of its next-generation Precise MRD test to patients with breast, colorectal and renal cancers, covering more than six million individuals living with these tumor types in the U.S. This expansion enables clinicians to monitor minimal residual disease across critical points, from neoadjuvant therapy through long-term surveillance.

The prospective MONITOR-Breast trial enrolled 154 Stage I–III breast cancer patients across all molecular subtypes and analyzed 949 plasma samples. Key findings include 93% ctDNA detection at baseline, 100% specificity for predicting pathological complete response, a 47-fold higher chance of persistent ctDNA post-surgery for those positive after neoadjuvant therapy, and identification of 44% more at-risk patients through longitudinal sampling.

Precise MRD employs whole-genome sequencing to generate personalized panels tracking up to 1,000 variants per patient, enabling ultrasensitive detection of circulating tumor DNA even in low-shedding tumors. Its design supports integration into academic and community oncology workflows for neoadjuvant monitoring, post-surgical assessment and ongoing surveillance.

This milestone aligns with Myriad’s precision oncology strategy to expand molecular monitoring across tumor types and build robust clinical evidence. The company anticipates that continued publication of clinical data and broader tumor coverage will cement Precise MRD’s role in guiding treatment decisions and improving risk stratification.