Three-Weekly S-1 Monotherapy as First-Line Treatment in Elderly Patients with Recurrent or Metastatic Gastric Cancer

Background/Aims: Elderly patients with advanced gastric cancer (AGC) have generally been excluded from clinical trials, and there are few data available on the treatment of these patients. The efficacy of palliative S-1 monotherapy as a first-line treatment regimen for elderly patients has not been well elucidated. Methods: For this study, 25 AGC patients were enrolled between January 1, 2007 and March 31, 2009; 4 cases were recurrent AGC and 21 cases were metastatic AGC at the time of diagnosis. These patients received S-1 therapy at a dose of 40 mg/m2 twice daily for 14 days every 3 weeks. All of the patients were older than 70 years. Results: The median follow-up duration, the median progression-free survival, and the overall survival time were 8.7 months (range, 4.9 to 12.5 months), 4.9 months (range, 3.5 to 6.3 months), and 10.8 months (range, 6.6 to 15.0 months), respectively. Grade 3/4 nonhematologic toxicities were rare. Grade 3/4 neutropenia was noted in two patients. The partial response rate was 21.7% and stable disease was observed in 34.8% of the patients. Two patients (8%) died due to chemotherapy-associated toxicity during treatment (septic shock/intracranial hemorrhage). Conclusions: Oral S-1 chemotherapy seems to be effective as a first-line treatment regimen for elderly patients with metastatic or recurrent AGC. However, elderly patients receiving S-1 treatment should undergo continuous toxicity monitoring, since they are highly susceptible to adverse effects. (Gut Liver 2010;4:503-507)