Compare S-1 for 9 Months to 1 Year as Adjuvant Chemotherapy in Stage II Gastric Cancer (SMAC）
The study aims to compare the efficacy and safety of S-1 for 9 months versus S-1 for 1 year as adjuvant chemotherapy after D2 resection in patients with gastric cancer. Hypothesis: For gastric patients after D2 resection, S-1 for 9 months shows non-inferiority to S-1 for 1 year in disease-free survival(DFS), overall survival (OS) and safety.
• The lower age limit of research subjects 18 years old and upper age limit of 75 years old.
• Be proven to be primary adenocarcinoma of gastric cancer and staged II by pathological evidence
• R0 surgery with lymphadenectomy
• Without any other malignancies
• ECOG (ECOG score standard) performance status of 0 or 1 and expected to survive more than 6 months
• No contraindications to chemotherapy, including normal peripheral blood routine, liver, and kidney function and electrocardiogram （WBC≥4.0 x 109 /L, NEU≥1.5 x 109 /L, PLT≥100 x 109 /L and HGB≥90g/L).