Survival benefit from S-1 as compared to Fluorouracil in Asian patients with advanced gastrointestinal cancer: a meta-analysis.

Whether S-1 could replace 5-Fluorouracil (5-Fu) or not in the treatment of advanced gastrointestinal (GI) cancer (including advanced gastric cancer [AGS] and metastatic colorectal cancer [mCRC]) in Asian patients has been controversial. This meta-analysis was performed to compare the activity, efficacy and toxicity of S-1-based versus 5-Fu-based chemotherapy in those Asian patients. Randomized controlled trials (RCTs) were identified by electronic search of Pubmed. Relevant abstracts were manually searched to identify relevant trials. A total of 2182 patients from eight RCTs were included, and our results demonstrated that S-1-based chemotherapy significantly improved overall survival (OS) (hazard ratio [HR], 0.87; 95% confidence interval [CI], 0.77-1.00) and overall response rate (ORR) (odds ratio [OR], 1.72; 95% CI, 1.09-2.70), but no significant progression-free survival (PFS) benefit was found between arms (HR, 0.87; 95% CI, 0.72-1.06). Subgroup analyses revealed that S-1-based chemotherapy significantly improved OS and ORR in subgroups of patients with non-platinum containing regimens (P = 0.041; P = 0.034) and patients with no prior chemotherapy history (P = 0.025; P = 0.016). Statistically significant improvements of PFS and ORR in the S-1-based chemotherapy were observed in the subgroup of patients with AGC (P < 0.001; P = 0.005). S-1-based chemotherapy was characterized by significantly higher incidences of diarrhea, fatigue and thrombocytopenia, and a lower incidence of nausea. This analysis provided strong evidence for survival benefits of S-1, and S-1-based chemotherapy could be considered to replace 5-Fu-based therapy for the treatment of advanced GI cancer in Asian patients.