Background The role of adjuvant chemotherapy in stage II colon cancer continues to be
debated. The presence of circulating tumor DNA (ctDNA) after surgery predicts very poor
recurrence-free survival, whereas its absence predicts a low risk of recurrence. The benefit
of adjuvant chemotherapy for ctDNA-positive patients is not well understood. Methods We
conducted a trial to assess whether a ctDNA-guided approach could reduce the use of
adjuvant chemotherapy without compromising recurrence risk. Patients with stage II colon …

108 Background: Previous results of the DYNAMIC study demonstrated that a ctDNA-guided
approach versus standard management in stage II colon cancer (CC) reduced adjuvant
chemotherapy (ACT) use without compromising 2-year recurrence-free survival (RFS). MMR
status defines two distinct subsets of stage II CC. Here, we report the impact of ctDNA
burden, end of ACT (EOT) ctDNA, and updated survival data including overall survival (OS).
Methods: DYNAMIC is a multi-center randomized phase II trial. Eligible patients (pts) had …