RESUMEN
Background: Nivolumab is an effective treatment option for advanced gastric cancer (GC). This study aimed to conduct a systematic review of existing literature to investigate the relationship between immune-related adverse events (irAEs) and the prognosis of patients with GC treated with nivolumab. Methods: We comprehensively searched four online literature databases: the Cochrane Central Register of Controlled Trials, PubMed, Embase, Web of Science, until 27 March 2024. The outcome measures of interest included: overall survival (OS), progression-free survival (PFS), hazard ratio (HR), median survival ratio (MSR), objective response rate (ORR), and disease control rate (DCR). Results: A total of six studies, including 393 patients, met the eligibility criteria. The OS (pooled hazard ratio [HR] = 0.4, 95% confidence interval [CI]: 0.3-0.6, p < 0.05) and PFS (pooled HR = 0.5, 95% CI: 0.4-0.6, p < 0.05) of patients with irAEs were significantly superior to individuals without irAEs. The MSR for OS and PFS were 2.5 (95% CI: 1.5-4.1, p < 0.05) and 2.8 (95% CI: 1.9-4.1, p < 0.05), respectively. Regarding the ORR and DCR, we found that the development of irAEs was significantly associated with higher rates: patients with irAEs had an ORR of 24.7% compared to 6.4% in those without irAEs (risk ratio [RR] = 2.6, p < 0.05), and a DCR of 86.0% compared to 30.3% in those without irAEs (RR = 3.2, p < 0.05). Conclusion: There appears to be a significant correlation between the development of irAEs and the better survival benefits with nivolumab in patients with GC. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42022341396.