A liquid biopsy-guided approach to treating stage II colon cancer can reduce reliance on adjuvant chemotherapy without jeopardising patient survival, a pivotal study suggests.

Melbourne-led authors say results from the DYNAMIC trial could further personalise oncological care, with the decision to treat predicated on presence of circulating tumour DNA (ctDNA).

Prior studies of localised colon cancer have consistently shown that ctDNA testing can reliably detect minimal residual disease post-surgery and predict recurrence, but its utility in guiding use of adjuvant chemotherapy is unclear.

To explore this, the researchers randomly assigned 455 patients (median age 64) with histologically confirmed stage II colon or rectal adenocarcinoma in a 2:1 ratio to treatment guided by ctDNA results or standard management.