ctDNA as a prognostic factor in operable colon cancer patients: a systematic review and meta-analysis.

Using circulating tumor DNA (ctDNA) instead of historical clinicopathological factors to select patients for adjuvant chemotherapy (ACT) may reduce inappropriate therapy. MEDLINE was searched on 31 March 2020. Studies, including data related to the prognostic value of ctDNA in the colon cancer patients after surgery and after ACT, were included. The generic inverse-variance method with a random-effects model was used for meta-analysis. Four studies were included for this meta-analysis. ctDNA-positive colon cancer patients after surgery and ACT had a significantly increased risk of recurrence compared with ctDNA-negative patients. ctDNA is an independent prognostic factor, and this meta-analysis is a significant step for using ctDNA instead of historical prognostic factors in the adjuvant setting.