Impact of postoperative complications on long-term outcomes of patients following surgery for gastric cancer: A systematic review and meta-analysis of 64 follow-up studies.

Gastrectomy for cancer is a technically demanding procedure, with postoperative complications (POCs) reported to be in the range of 20%-46%. However, the effect of POCs on long-term survival of gastric cancer patients following surgery is far from conclusive. This systemic review aimed to determine the impact of postoperative complications (POCs) on the long-term survival of patients following surgery for gastric cancer. A systematic electronic search of PubMed and Scopus was performed from inception to June 26, 2018 to identify studies that described the relationship between POCs and long-term survival. Hazard ratios (HRs) for overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) from each study were combined using a random-effects model. Sixty-four eligible studies with reported results for 46198 gastric cancer patients were included. A meta-analysis found a statistically significant difference in OS, CSS and RFS between gastric patients with unspecific POCs and no POCs, POCs ≥ Clavien-Dindo grade (CD) 2 and < CD2, major POCs and minor POCs, infectious and non-infectious complications, anastomotic and non-anastomotic complications, and cardiopulmonary and non-cardiopulmonary complications. Subgroup and sensitivity analyses did not significantly change the summary of OS risk estimates between patients with POCs and without POCs. No significant publication bias was observed for the same outcome. The meta-analysis revealed that POCs were associated with worse survival among patients with resected gastric cancer, suggesting that treatment strategies aimed at minimizing POCs may improve oncological outcomes.