Background: Adjuvant chemotherapy (AC) regimens tegafur/gimeracil/oteracil (S-1) and capecitabine plus oxaliplatin (CAPOX) have predominated, however, there has been a lack of studies on their differences in efficacy. Methods: We conducted pairwise meta-analyses comparing the efficacy of S-1 and CAPOX regimens for overall survival (OS) and disease-free survival (DFS) in stage II or III GC patients. Results: Three studies were enrolled and analyzed using a forest plot for meta-analysis. Two of them were propensity score matching studies, and the remaining one was a retrospective observational study. In all stages, the five-year OS was not different between the two regimens (HR 0.96, 95% CI 0.78-1.17; p = 0.56). Additionally, the 5-year DFS was not different at any stage (HR 1.00, 95% CI 0.85-1.18; p = 0.21). After omitting the retrospective observational study, the five-year OS (HR 1.40, 95% CI 0.53-3.73) and DFS (HR 1.41, 95% CI 0.57-3.44) of S-1 tended to be better in stage II, and the five-year OS (HR 0.81, 95% CI 0.56-1.16) and DFS (HR 0.85, 95% CI 0.63-1.13) of CAPOX tended to be better in stage III, without statistical significance. Conclusions: In the present meta-analysis, the five-year OS and DFS for stage II or III GC patients were comparable between S-1 and CAPOX regimens as AC.
Keywords: CAPOX; S-1; adjuvant chemotherapy; gastric neoplasm; survival.