Circulation tumour DNA in predicting recurrence and prognosis in operable colorectal cancer patients: A meta‐analysis

Abstract Background Selecting the appropriate patient for further treatment after surgery and adjuvant chemotherapy (ACT) for colorectal cancer (CRC) can improve the patient's prognosis. Circulating tumour DNA (ctDNA) has the potential to predict recurrence and prognosis after CRC surgery and ACT, but the results are still inconclusive. Objectives As the completed studies have small sample sizes and different experimental methods, a meta‐analysis was conducted to assess the ctDNA on recurrence and prognosis after CRC surgery and ACT. Methods PubMed, Embase, the Web of Science and the Cochrane Library were searched for potentially eligible studies published up to 6 March 2022. Pooled relative risk (RR) and pooled hazard ratio (HR) were calculated to evaluate recurrence and the prognosis of recurrence‐free survival (RFS) following CRC surgery and ACT. Results Fourteen studies published between 2014 and 2022 included 2393 patients, and 7189 serum samples were eventually included in the meta‐analysis. The pooled revealed that ctDNA‐positive patients were at high risk of recurrence after CRC surgery (RR = 4.43, 95% CI: 3.58–5.48, p < .05) and had a poorer prognosis for RFS (HR = 7.26, 95% CI: 5.48–9.62, p < .05). The pooled revealed that ctDNA‐positive patients were at high risk of recurrence after ACT (RR = 5.77 95% CI: 4.33–7.69, p < .05) and had a poorer prognosis for RFS (HR = 13.96, 95% CI: 8.71–22.4, p < .05). Conclusion ctDNA‐positive patients were at a high risk of recurrence after CRC surgery and ACT and had a poorer prognosis. Hence, ctDNA‐positive patients required close follow‐up and further treatments.