Circulating tumor DNA predicts recurrence and assesses prognosis in operable gastric cancer: A systematic review and meta-analysis

BACKGROUND: Selecting the appropriate patient for further treatment after surgery for gastric cancer can improve the patient prognosis. Circulating tumor DNA (ctDNA) has the potential to predict recurrence and prognosis after gastric cancer surgery, but the results are still inconclusive. As the completed studies had small sample sizes and were inconsistent, a meta-analysis was conducted to assess the effect of ctDNA on recurrence and prognosis after gastric cancer surgery. METHODS: PubMed, Embase, Scopus, and the Web of Science were searched for potentially eligible studies published up to April 7, 2023. Pooled relative risk (RR) and pooled hazard ratio (HR) were calculated to evaluate recurrence, recurrence-free survival (RFS), and overall survival (OS) following gastric cancer surgery. RESULTS: A pooled analysis revealed that patients who were ctDNA positive before and after surgery were at a high risk of gastric cancer recurrence (RR = 1.79, 95% CI: 1.19–2.71; RR = 3.17, 95% CI: 2.36–4.25). The pooled data revealed that ctDNA-positive patients had a poorer RFS and OS (HR = 6.37, 95% CI: 2.70–15.01; HR = 4.58, 95% CI: 1.68–12.49). CONCLUSIONS: ctDNA-positive patients were at a high risk of recurrence after gastric cancer surgery and had a poorer prognosis. Hence, ctDNA-positive patients needed close follow-up and further treatment.