S-1-based vs non-S-1-based chemotherapy in advanced gastric cancer: A meta-analysis

AIM: To assess the efficacy and tolerability of S-1-based vs non-S-1-based chemotherapy in advanced gastric cancer (AGC).METHODS: We extracted reported endpoints, including overall survival (OS), progression-free survival (PFS), time-to-treatment failure (TTF), objective response rate (ORR) and adverse effects, from randomized controlled trials identified in PubMed, the Cochrane library, Science Direct, EMBASE and American Society of Clinical Oncology meetings. Stata software was used to calculate the pooled values.RESULTS: Seven randomized controlled trials involving 2176 patients were included in this meta-analysis. Compared to non-S-1-based regimens, the use of S-1-based regimens were associated with an increase in ORR (RR = 1.300; 95%CI: 1.028-1.645); OS (HR = 0.89; 95%CI: 0.81-0.99; P = 0.025), TTF (HR = 0.83; 95%CI: 0.75-0.92; P = 0.000), and a lower risk of febrile neutropenia (RR = 0.225; P = 0.000) and stomatitis (RR = 0.230; P = 0.032). OS, PFS and TTF were prolonged, especially in the Asian population. In subgroup analysis, statistically significant increases in ORR (RR = 1.454; P = 0.029), OS (HR = 0.895; P = 0.041) and TTF (HR = 0.832; P = 0.000) were found when S-1-based chemotherapy was compared to 5-fluorouracil (5-FU)-based chemotherapy. The incidence of leukopenia (RR = 0.584; P = 0.002) and stomatitis (RR = 0.230; P = 0.032) was higher in the 5-FU-based arm. S-1-based regimens had no advantage in ORR, OS, PFS, TTF and grade 3 or 4 adverse events over capecitabine-based regimens.CONCLUSION: S-1-based chemotherapy may be a good choice for AGC because of longer survival times, better tolerance and more convenient use.