According to an article recently published in the New England Journal of Medicine, treatment with the chemotherapy agent S-1 following surgery for Stages II-III gastric cancer improves survival compared with surgery alone with acceptable side effects.
Gastric cancer refers to cancer of the stomach. Standard treatment for gastric cancer is determined by the stage (extent of spread) of the cancer but typically consists of surgery to remove as much of the cancer as possible, followed by chemotherapy. A standard chemotherapy regimen for treatment of gastric cancer is the fluoropyrimidine agent 5-fluorouracil(5-FU). 5-FU is administered intravenously. However, the addition of chemotherapy to standard treatment has remained controversial, as not all trials have demonstrated an improved survival with the addition of chemotherapy to surgery compared with surgery only.
S-1 is an oral agent that is converted to 5-FU in the body. It also contains gimeracil, which helps to inhibit the degredation of 5-FU in the body, and oteracil, which helps to reduce gastrointestinal side effects normally caused by 5-FU. S-1 has demonstrated effectiveness when used as a chemotherapy agent, but is not approved in the United States.
Researchers from Japan recently conducted a clinical trial to further evaluate the use of S-1 in the treatment of early gastric cancer. This trial included 529 patients with Stages II-III gastric cancer (cancer has spread either nearby lymph nodes or structures, but not to distant sites in the body). Patients were treated with either surgery alone to remove the stomach and lymph nodes or surgery plus S-1.
- At three years overall survival was 80% for patients treated with S-1 compared with 70% for those treated with surgery only.
- Side effects associated with S-1 included nausea, diarrhea, and weight loss.
- The trial was stopped early upon recommendation from the safety monitoring committee at its first analysis due to the significant improvement in survival for patients treated with S-1.
- The researchers concluded that the addition of S-1 to surgery for Stages II-III gastric cancer significantly improves survival compared with surgery alone.
Patients diagnosed with gastric cancer may wish to speak with their physician regarding their individual risks and benefits of participating in a clinical trial further evaluating S-1 or other novel therapeutic approaches.
Reference: Sakuramoto S, Sasako M,Yamaguchi T, et al. Adjuvant Chemotherapy for Gastric Cancer with S-1, an Oral Fluoropyrimidine. New England Journal of Medicine. 2007;357:1810-1820.