This meta-analysis will be performed to evaluate the safety and efficacy of biweekly CPT-11 plus CDDP versus CPT-11 alone in patients with advanced gastric cancer (AGC) who had received S-1-based first-line chemotherapy. Individual patient-level data from two prospective randomized trials employing the same regimens in the second-line setting for advanced or recurrent gastric cancer will be collected for the study. The primary endpoint is overall survival. Subset analysis will be performed to identify differences in 1) cases with metastatic progression or early relapse after adjuvant chemotherapy, 2) previous platinum therapy, and 3) histological intestinal or diffuse type. Cumulative data from 298 patients will help define a better regimen for S-1 failure cases and might give an important information in selecting a more suitable regimen for subsets of patients.