ctDNA-Guided Adjuvant Therapy in Stage III Colon Cancer: Prognostic Validation but No Benefit from Chemotherapy Intensification — Key Findings from the DYNAMIC-III Randomized Phase 2/3 Trial

Highlight

• DYNAMIC-III (Tie et al., Nat Med 2025) enrolled 968 evaluable stage III colon cancer patients and demonstrates that plasma ctDNA measured 5–6 weeks after surgery is a powerful prognostic classifier: 3-year recurrence-free survival (RFS) was 87% for ctDNA-negative versus 49% for ctDNA-positive patients (P < 0.001).

• In ctDNA-negative patients, a ctDNA-guided de-escalation strategy markedly reduced oxaliplatin exposure (34.8% vs 88.6%) and hospitalizations (8.5% vs 13.2%) but did not meet the non-inferiority margin for RFS (85.3% vs 88.1%).