Characteristics of included studies.

Objective
To assess S-1 and 5-fluorouracil (5-FU)-related adverse events in patients with advanced gastric cancer and provide focused health care approaches to improve patient compliance and quality of survival.
Methods
The PubMed, Web of Science, Medline, Cochrane Library, EMbase, SinoMed, Wan Fang Data, CNKI, and VIP databases were searched, and relevant literature was screened from the database construction date through March 31, 2023. Review Manager 5.4.1 and Stata 12.0 were used to analyze the data and GRADEpro was used to assess the quality of the literature. Relative risk ratio (RR) and a 95% confidence interval (CI) were employed as markers to compare adverse events due to S-1 vs 5-FU.
Results
Eight randomized controlled trials (RCT) were included, which contained 3,455 patients. The S-1 group had 1,804 patients, and the 5-FU group had 1,651 patients. There were 17 recorded adverse events in total. Stomatitis, hypokalemia, mucosal inflammation, and hypophosphatemia were more common in the 5-FU group than in the S-1 group (P < 0.001). No significant difference was observed between S-1 and 5-FU for other adverse events.
Conclusions
Although both S-1 and 5-FU cause a variety of side effects, 5-FU resulted in a higher incidence of stomatitis, hypokalemia, mucosal inflammation, and hypophosphatemia than S-1. Medical professionals should closely monitor the occurrence of adverse drug events and provide timely, rational guidance and nursing care to improve patient compliance and quality of life.

研究目的 评估晚期胃癌患者中S-1与5-氟尿嘧啶（5-fluorouracil, 5-FU）相关不良事件，并制定针对性医疗照护策略以改善患者依从性与生存质量。
研究方法 检索PubMed、Web of Science、Medline、Cochrane图书馆、EMbase、SinoMed、万方数据、中国知网（CNKI）及VIP数据库，检索时限为各数据库建库起至2023年3月31日，筛选相关文献。采用Review Manager 5.4.1与Stata 12.0开展数据分析，使用GRADEpro评估文献质量。以相对危险度(Relative risk ratio, RR)及95%置信区间(95% confidence interval, CI)作为效应指标，对比S-1与5-FU相关不良事件的发生情况。
研究结果 共纳入8项随机对照试验(randomized controlled trials, RCT)，涉及3455例患者，其中S-1组1804例，5-FU组1651例。总计记录17种不良事件。5-FU组口腔炎、低钾血症、黏膜炎症及低磷血症的发生率显著高于S-1组（P < 0.001）；其余不良事件在两组间差异无统计学意义。
研究结论 尽管S-1与5-FU均可引发多种不良反应，但5-FU所致口腔炎、低钾血症、黏膜炎症及低磷血症的发生率显著高于S-1。临床医护人员应密切监测药物不良事件的发生，及时提供合理的指导与护理干预，以提升患者依从性与生活质量。