Safety and efficacy of S-1 treatment in elderly patients with advanced or recurrent gastric cancer: A subgroup analysis from the phase III JFMC36-0701 trial

Abstract

Background: Chemotherapy is often considered for elderly patients with advanced or recurrent gastric cancer. However, there are no prospective trials evaluating outcomes of chemotherapy in elderly patients with gastric cancer. Safety and efficacy of S‐1 treatment in elderly versus younger patients were evaluated in the phase III JFMC36‐0701 trial. Methods: Between February 2007 and June 2010, 309 patients with advanced or recurrent gastric cancer were randomly assigned to S‐1alone or S‐1plus lentinan treatment; 134 patients (43.4%) enrolled were≥75 years of age (range, 75‐94) and 175 (56.6%) were<75 years of age (range, 30‐74). S‐1 was given orally in the dose of 40 mg/m2 twice daily for the first 4 weeks of a 6‐week cycle. Lentinan was given as an intravenous infusion of 2 mg/body every week. Overall survival (OS), overall response rate (ORR) and safety were compared between patients aged≥75 and<75 years. Results: Patient characteristics were comparable between the two cohorts. OS was 12.8 (95% CI 10.7‐14.9) and 11.5 (95% CI 9.5‐13.4) months for patients aged ≥75 and<75 years, respectively with no statistical difference. The ORR was evaluable in the 190 patients with measurable disease at baseline. The ORR was 23.4% and 18.6% in patients aged≥75 and<75 years, respectively. Disease control rates were also similar: 44.2% versus 48.7% for elderly versus younger patients. Rates of neutropenia (≥grade3) were comparable for elderly and younger patients (12.7% versus 10.4%), and the incidences of non‐hematologic adverse events (≥grade3) such as anorexia, vomiting and fatigue were also similar in both elderly and younger patients (12.7% versus 10.4%, 0% versus 1.8% and 7.9% versus 4.9%, respectively). Conclusions: This subgroup analysis suggests that elderly patients with advanced or recurrent gastric cancer derive similar benefit from S‐1 treatment to younger patients, with acceptable toxicity.