Discussion
tumour, resected stage II colon cancer
RECRUITMENT, TUMOUR, RECTAL CANCER
We describe the protocol of the multi-centre, prospective, randomised trial designed to compare the 3 year DFS in patients with high risk stage II and stage III fully resected colon and rectal cancers treated with ctDNA guided ACT versus SOC chemotherapy, sponsored by the Royal Marsden Hospital NHS Foundation Trust, London. The study builds on the results from TRACC Part B; the observational, prospective, translational research study involving serial blood sampling for ctDNA pre- and post-operatively, which demonstrated an improved 12 and 24 month RFS in patients who were ctDNA negative post-operatively.TRACC Part C is the only ctDNA-guided study of ACT in CRC running in the UK and addresses a research question with significant health economic importance. The DYNAMIC II study is the only reported study in this space to date globally, which provided evidence to support the de-escalation of ACT in patients with resected stage II colon cancer [TRACC Part C is one of the only ctDNA-guided studies using a plasma-only tumour-naïve ctDNA assay for MRD detection in CRC globally. Utilising a blood-only assay with a turnaround time of 7-14 days, where analysis of tumour tissue is not required, lends itself to a more streamlined approach to recruitment within the study, as well as smooth potential future implication into standard clinical practice. The inbuilt patient reported outcomes (PROs), health economic analysis and process evaluation will provide a route to effective implementation in SOC clinical practice within the NHS and elsewhere in the future.