ASCO 2025 | What is the future role of ctDNA as a biomarker in colorectal cancer?

A lot of wonderful progress on circulating tumor DNA showing the potential to really identify patients for optimal chemotherapy utilization in the adjuvant setting as well as identifying patients that may benefit from EGFR re-challenge. So we had two studies that, while they’re negative on their primary endpoint, showed very compelling activity and utility of the ctDNA biomarkers. So the DYNAMIC-III study was looking at it, reporting out an escalation arm, and really showed that the ctDNA defined an incredibly high-risk population. In this population, escalation of therapy from three to six months of FOLFOX or the addition of irinotecan and cetuximab in this smaller phase two study didn’t improve the disease-free survival, but did really define a population in need of novel therapies. The subsequent study in metastatic disease looking at EGFR re-challenge demonstrated really good activity of the EGFR re-challenge, especially when combined with the full FOLFIRI regimen in patients who were ctDNA selected to not have any additional secondary mutations. While the study did not meet its overall survival, it did show a very nice response rate and disease control with this approach. Really reiterating the fact that this is a standard care option, both for using ctDNA to monitor adjuvant and understanding prognosis in the postoperative period, but also using genotype-directed ctDNA to help define patients that may benefit from EGFR re-challenge.

This transcript is AI-generated. While we strive for accuracy, please verify this copy with the video.