Postoperative complications and prognosis after radical gastrectomy for gastric cancer: a systematic review and meta-analysis of observational studies

BACKGROUND: Many observational studies have reported correlations between postoperative complications and prognosis after radical gastrectomy but the results are controversial. This meta-analysis was performed to investigate whether there is a correlation between postoperative complications and prognosis after radical gastrectomy. METHODS: Literature searches were performed in PubMed, EMBASE, and the Cochrane Library. Studies that investigated the correlations between any postoperative complications and prognosis after radical gastrectomy were included. The pooled hazard ratio (HR) with 95% confidence interval (CI) for postoperative complications regarding overall survival (OS) or recurrence-free survival (RFS) was calculated by using RevMan 5.3.5. Subgroup analyses were performed within pathological stages I, II, and III. RESULTS: Sixteen retrospective studies comprising 12,065 patients were included. The pooled HR (95% CI) for complications regarding OS was 1.79 (1.39, 2.30) and was 1.40 (1.06, 1.84) after excluding in-hospital mortality; the pooled HR (95% CI) for complications regarding RFS was 1.28 (1.10, 1.49). The pooled HR (95% CI) for infectious complications and leakage regarding OS was 1.86 (1.22, 2.83) and 2.02 (1.02, 4.00), respectively. The pooled HR (95% CI) for any reported postoperative complications regarding OS for stage I, II, and III diseases was 2.39 (0.77, 7.46), 4.35 (2.58, 7.35), and 2.84 (1.77, 4.56), respectively. CONCLUSIONS: Postoperative complications correlate with poor prognosis after radical gastrectomy. Such correlations are found in stage II and III gastric cancer patients but remain to be determined in stage I gastric cancer patients. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s12957-019-1593-9) contains supplementary material, which is available to authorized users.