Background: Palliative chemotherapy has been shown to have a survival benefit for patients with recurrent or metastatic gastric cancer. We conducted a Phase II trial to determine the efficacy and safety of S-1 plus oxaliplatin (SOX regimen) as first-line chemotherapy for patients with unresectable locally advanced or metastatic gastric cancer.
Methods: Eligible patients had measurable lesions and no previous history of chemotherapy (except adjuvant chemotherapy). Oxaliplatin was administered intravenously at a dose of 130 mg/m(2) on day 1. S-1 was administered orally in doses of 80, 100, or 120 mg/d according to body surface areas of <1.25 m(2), 1.25-1.5 m(2), or >1.5 m(2) respectively; the total dose was divided into two daily doses on days 1-14. Treatments were repeated every 3 weeks until disease progression or intolerable toxicity occurred.
Results: Forty-three patients were enrolled in the study. All were assessable for efficacy and adverse events. The objective response and disease control rates were 55.8% and 76.7% respectively. The median follow-up time was 16.5 months. The median progression-free survival time was 7 months (95% CI, 5.8-8.2 months) and the median overall survival time was 16.5 months (95% CI, 9.7-23.3 months). The one-year survival rate was 54.2%. Major adverse reactions were grade 3/4 neutropenia (9.3%) and thrombocytopenia (20.9%).
Conclusion: The SOX regimen with oxaliplatin at a dose of 130 mg/m(2) was found to be effective and safe as a first-line chemotherapy in Chinese patients with advanced gastric cancer.