Circulating tumor DNA analysis guiding adjuvant therapy in stage II colon cancer: five-year outcomes of the randomized DYNAMIC trial

Early data from the DYNAMIC study of circulating tumor DNA (ctDNA)-guided adjuvant chemotherapy (ACT) versus standard approach met its primary outcome demonstrating reduced ACT use without compromising 2-year recurrence free survival (RFS) among patients with stage II colon cancer. Long-term outcomes of the study have now been published. At a median follow-up of 59.7 months, the 5-year RFS was 88% and 87% with ctDNA-guided and standard management, respectively, while 5-year overall survival was 93.8% versus 93.3%. Among treated ctDNA-positive patients, ctDNA clearance at the end of ACT was observed in 87.5% of patients. ctDNA-clearance was associated with 5-year recurrence-free probability of 97%, compared with 0% for ctDNA persistence. The authors conclude that mature DYNAMIC outcome data support a ctDNA-guided approach to ACT for stage II colon cancer.