Efficacy of Chemoimmunotherapy versus Chemotherapy for Gastric Cancer: A Meta-Analysis of Survival Outcomes

Background: Gastric cancer has been traditionally treated with chemotherapy as the primary mode of treatment. However, recent studies have shown that chemoimmunotherapy is also effective and, in some cases, better than chemotherapy treatment. Current study aimed to find the efficacy of chemoimmunotherapy versus chemotherapy in the treatment of gastric cancer. Methods: Using electronic databases, including PubMed, Embase, and EBSCO, a thorough literature search was carried out for the years 2006 to 2023. The search strategy was designed to identify relevant studies based on chemoimmunotherapy and chemotherapy intervention, and the search was conducted using appropriate keywords and MeSH terms. The retrieved studies were screened for relevance based on their titles, abstracts, and full texts. The studies' inclusion criteria were predefined, and the selected studies were then subjected to a quality assessment using GradePro GDT. The data from selected studies were extracted and analyzed using Revman version 5.4. Results: The study found that chemoimmunotherapy treatment resulted in a significant improvement in overall survival (OS) with a risk ratio (RR) of 1.54 and a 95% Confidence Interval (CI) of 1.25 to 1.89. The overall effect was also found to be significant, with a p-value of less than 0.001. Furthermore, we also observed an improvement in the 1-year, 3-year, and 5-year survival rates with risk ratio (RR) of 1.09 (95% CI: 1.01, 1.17), 1.43 (95% CI: 1.28, 1.60), and 1.59 (95% CI: 1.10, 2.30), respectively. In addition, it's also found that chemoimmunotherapy treatment also resulted in an improvement in DFS with an RR of 1.94 and a 95% CI of 1.44 to 2.59. Overall, these results suggest that chemoimmunotherapy treatment can be an effective approach in comparison to chemotherapy for improving overall survival and disease-free survival in the studied population. Conclusion: This study comparing chemoimmunotherapy versus chemotherapy for gastric cancer showed that both treatments were effective, but chemoimmunotherapy had more significant efficacy. To support these results, additional studies with a large sample size and a longer follow-up time are required.