The Evolving Role of ctDNA in Colorectal Cancer: Updates from ASCO 2025

Anita Turk, MD, medical oncologist at IU Health, discusses how circulating tumor DNA (ctDNA) plays a role in the management of colorectal cancer, as seen in abstracts presented at the 2025 ASCO Annual Meeting.

Important updates included the DYNAMIC-III trial (ACTRN12617001566325), which included patients with stage III colon cancer who were ctDNA-positive after undergoing resection.

"This clearly showed the prognostic importance of checking ctDNA in the postoperative setting, demonstrating the poor outcomes these patients have even after a period of initial therapy," Turk says. "We know this is a really, really high-risk population. At the end of the day, the data still doesn't really show that intensification of therapy is salvaging these patients, which kind of makes sense. If your ctDNA is positive, you get chemotherapy, and you still remain positive, we're not seeing improved outcomes by adding more chemotherapy." Turk notes that this is an unmet need in the space, and researchers and clinicians need to determine the right approach for these patients.