Adjuvant chemotherapy for gastric cancer with S-1, an oral fluoropyrimidine

N Engl J Med. 2007 Nov 1;357(18):1810-20. doi: 10.1056/NEJMoa072252.


Background: Advanced gastric cancer can respond to S-1, an oral fluoropyrimidine. We tested S-1 as adjuvant chemotherapy in patients with curatively resected gastric cancer.

Methods: Patients in Japan with stage II or III gastric cancer who underwent gastrectomy with extended (D2) lymph-node dissection were randomly assigned to undergo surgery followed by adjuvant therapy with S-1 or to undergo surgery only. In the S-1 group, administration of S-1 was started within 6 weeks after surgery and continued for 1 year. The treatment regimen consisted of 6-week cycles in which, in principle, 80 mg of oral S-1 per square meter of body-surface area per day was given for 4 weeks and no chemotherapy was given for the following 2 weeks. The primary end point was overall survival.

Results: We randomly assigned 529 patients to the S-1 group and 530 patients to the surgery-only group between October 2001 and December 2004. The trial was stopped on the recommendation of the independent data and safety monitoring committee, because the first interim analysis, performed 1 year after enrollment was completed, showed that the S-1 group had a higher rate of overall survival than the surgery-only group (P=0.002). Analysis of follow-up data showed that the 3-year overall survival rate was 80.1% in the S-1 group and 70.1% in the surgery-only group. The hazard ratio for death in the S-1 group, as compared with the surgery-only group, was 0.68 (95% confidence interval, 0.52 to 0.87; P=0.003). Adverse events of grade 3 or grade 4 (defined according to the Common Toxicity Criteria of the National Cancer Institute) that were relatively common in the S-1 group were anorexia (6.0%), nausea (3.7%), and diarrhea (3.1%).

Conclusions: S-1 is an effective adjuvant treatment for East Asian patients who have undergone a D2 dissection for locally advanced gastric cancer. ( number, NCT00152217 [].).

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Antimetabolites, Antineoplastic / adverse effects
  • Antimetabolites, Antineoplastic / therapeutic use*
  • Chemotherapy, Adjuvant
  • Disease-Free Survival
  • Drug Combinations
  • Female
  • Follow-Up Studies
  • Humans
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Neoplasm Metastasis / prevention & control
  • Neoplasm Recurrence, Local / epidemiology
  • Neoplasm Staging
  • Oxonic Acid / adverse effects
  • Oxonic Acid / therapeutic use*
  • Stomach Neoplasms / drug therapy*
  • Stomach Neoplasms / mortality
  • Stomach Neoplasms / surgery
  • Survival Rate
  • Tegafur / adverse effects
  • Tegafur / therapeutic use*


  • Antimetabolites, Antineoplastic
  • Drug Combinations
  • S 1 (combination)
  • Tegafur
  • Oxonic Acid

Associated data