The largest published study of molecular residual disease (MRD) in stage III colon cancer shows that Guardant Health’s ctDNA blood test can more precisely identify which patients are likely to experience recurrence after surgery.
In a study of more than 2,000 patients, about 20% had detectable circulating tumor DNA after surgery—and these patients faced a four-to-six-fold higher risk of recurrence or death. Even patients considered lower risk by conventional staging showed significantly worse outcomes when ctDNA was present.
The findings suggest that liquid biopsy may soon become a routine tool for guiding adjuvant therapy, surveillance intensity, and personalized treatment decisions after surgery.
For oncology and GI leaders, the message is clear: postoperative cancer care is shifting from anatomy-based staging to molecular-level risk stratification.