Multicenter phase II study of S-1 and docetaxel combination chemotherapy for advanced or recurrent gastric cancer patients with peritoneal dissemination

Purpose: Peritoneal dissemination is the most frequent and life-threatening mode of metastasis and recurrence in patients with gastric cancer. A multicenter phase II study was designed to evaluate the efficacy and tolerability of S-1 and docetaxel combination chemotherapy regimen for the treatment of advanced or recurrent gastric cancer patients with peritoneal dissemination. Methods: Nineteen patients with histologically confirmed unresectable or recurrent gastric cancer with peritoneal dissemination were enrolled. Oral S-1 at 80 mg/m²/day was administered twice daily for 2 weeks, followed by 1 drug-free week. Docetaxel infusion at 40 mg/m² was performed on day 1, simultaneous with S-1 administration. The primary endpoints were overall survival (OS) and time to progression (TTP). The secondary endpoints were the response rates and safety status. Results: Patients received a median of 4 cycles of the S-1 and docetaxel regimen (range 1-43). The disease control rate was 73.7 % (14/19). Median overall survival was 459 days (15.3 months), while median time to progression was 212 days (7.1 months). Neutropenia was the most common type of toxicity (n = 7, 36.8 %). Conclusions: Combination chemotherapy with S-1 and docetaxel is a tolerable and effective treatment for advanced or recurrent gastric cancer patients with peritoneal dissemination.