Oxaliplatin + S-1 is a recognized treatment regimen in Japan, but there are no Japanese clinical data on an oxaliplatin dose of 130 mg/m2. The current research involves a single-arm, prospective, phase II clinical trial to examine the efficacy and safety of oxaliplatin + S-1 with an oxaliplatin dose of 130 mg/m2 to treat HER2-negative advanced/recurrent gastric cancer previously untreated with chemotherapy in Japan. | Study protocol of a phase II clinical trial KSCC1501A examining oxaliplatin S-1 for treatment of HER2-negative advanced recurrent gastric cancer previously untreated with chemotherapy