Comparing 9 Months Versus 1 Year of S-1 Chemotherapy After D2 Surgery in Stage II Gastric Cancer

What this Trial Is About

Researchers are evaluating the safety and effectiveness of two different durations of S-1 chemotherapy as additional treatment after surgery in patients with stage II gastric cancer. This study compares taking S-1 for 9 months versus taking it for 1 year following D2 lymph node dissection surgery. The goal is to see if 9 months of treatment is not worse than 1 year in terms of disease-free survival, overall survival, and safety. Participants will be randomly assigned to receive S-1 chemotherapy either for 9 months or for 1 year. Both groups will follow a treatment cycle of taking S-1 daily for 14 days, followed by a 7-day rest, repeating every 3 weeks. The dose of S-1 ranges from 80 to 120 mg per day. The study includes planned interim analyses to monitor safety and progress, with a final assessment after five years from the last patients enrollment. During the study, participants will have regular monitoring to assess disease-free survival at 3 years and overall survival at 5 years, as well as safety evaluations. Organ function and blood tests will be checked to ensure participants tolerate the treatment. The study aims to provide new guidance on the optimal duration of S-1 chemotherapy after surgery for gastric cancer, with involvement lasting several years including follow-up.

S-1 for 9 Months Versus 1 Year for Stage II Gastric Cancer (SMAC）