Dr Tie talks to ecancer at ESMO 2025 about data she presented from the randomised phase II/III DYNAMIC-III trial.

This evaluated a circulating tumour DNA (ctDNA)-guided approach to tailor adjuvant chemotherapy (ACT) in patients with stage III colon cancer. Among 968 evaluable participants, 702 (72.5%) were ctDNA-negative post-surgery and randomized to ctDNA-guided or standard management. In the ctDNA-guided arm, 90% of patients underwent chemotherapy de-escalation, resulting in markedly reduced oxaliplatin use (34.8% vs 88.6%) and fewer grade ≥3 adverse events (6.2% vs 10.6%) and hospitalisations (8.5% vs 13.2%) compared to standard management. 

While non-inferiority for 3-year recurrence-free survival was not formally met (85.3% vs 88.1%), outcomes were closely aligned, particularly in clinical low-risk tumours (T1–3N1). 

Dr Tie concludes that these findings demonstrate the feasibility and safety of ctDNA-guided de-escalation, supporting a precision approach to minimize overtreatment in ctDNA-negative stage III colon cancer.