A phase II study of combination therapy with oral S-1 and cisplatin in elderly patients with advanced gastric cancer

Abstract

Background: A combination of S-1 and cisplatin is recognized as one of the standard first-line chemotherapy regimens for patients with advanced gastric cancer. However, demographic analyses of pivotal phase III studies have showed that only a minority of treated patients were aged 76 years or older. The purpose of this phase II study was to evaluate the safety and efficacy of combination therapy with S-1 and cisplatin in elderly patients with chemotherapy-naive advanced gastric cancer. Methods: Patients aged 76 years or older received S-1 40 mg/m2 orally twice daily for 21 days and cisplatin 60 mg/m2 intravenously infused at day 8 of each 35-day cycle. Dose modification was performed according to creatinine clearance. The primary endpoint was overall survival (OS). Secondary endpoints included response rate, progression-free survival (PFS), time to treatment failure (TTF), and adverse events. Results: A total of 40 patients were enrolled. Median OS was 12.3 months, PFS was 7.8 months, and TTF was 4.3 months. The response rate was 54%. The most common grade 3–4 adverse events were anorexia (25%), neutropenia (23%), hyponatremia (20%), anemia (18%), and febrile neutropenia (8%). No treatment-related death occurred. Conclusions: Combination chemotherapy with S-1 and cisplatin is an effective and well-tolerated regimen for elderly patients with advanced gastric cancer when the dose is adjusted according to renal function.