The main objective of this study is to demonstrate that de-escalation/excalation treatment strategy for patients with stage III colon cancer using ctDNA informed management is non-inferior to standard of care treatment as measured by the rate of 3-year recurrence-free survival. (Please refer to DYNAMIC-III Protocol Version 2 Amendment -Summary of Major Changes, Section-5 - Study Objectives). Dynamic-III is a prospective, multi-centre, phase II/III randomised study aiming to enrol 1000 stage III colon cancer participants. The participants will be randomised 1:1 and treated according to post-operative ctDNA results (ctDNA informed), or per standard of care (COC) -refer to Protocol page 13, section 2 - Study Design): -As per standard of care (Arm A: SOC) or, - According to post-operative ctDNA results (Arm B: ctDNA informed) In the SOC are, patients/clinicians will be blinded to ctDNA results (Arm B: ctDNA informed) In the SOC arm, patients/clinicians will be blined to ctDNA results and will recieve adjuvant chemotherapy as per standard of care. Patients will be screeened post-surgery. Refer to attached original NEAF v2.2, Part 1, Q2 for further details. Refer to attached protocol Version 2 Amendment - SUmmary of Major Changes, Section 16.