Phase I/II study of intraperitoneal docetaxel plus S-1 for the gastric cancer patients with peritoneal carcinomatosis

PURPOSE: We designed a phase I/II trial of intraperitoneal (IP) docetaxel plus S-1 to determine the maximum tolerated dose (MTD) and recommended dose (RD) and to evaluate its efficacy and safety in gastric cancer patients with peritoneal carcinomatosis (PC). METHODS: Patients with PC confirmed by laparoscopy or laparotomy received IP docetaxel on days 1 and 15 and S-1 (80 mg/m(2)) on days 1–14 every 4 weeks. RESULTS: In the phase I part (n = 12), each cohort received escalating doses of docetaxel (35–50 mg/m(2)); the MTD was determined to be 50 mg/m(2) and the RD was determined to be 45 mg/m(2). Dose-limiting toxicities included grade 3 febrile neutropenia and grade 3 diarrhea. In the phase II part (n = 27), the median number of courses was 4 (range 2–11). The 1-year overall survival (OS) rate was 70 % (95 % confidence interval 53–87 %). The overall response rate was 22 % and peritoneal cytology turned negative in 18 of 22 (81 %) patients. The most frequent grade 3/4 toxicities included anorexia (19 %), neutropenia (7 %), and leukopenia (7 %). CONCLUSION: IP docetaxel plus S-1 is active and safety in gastric cancer patients with PC.