Phase II trial of postoperative adjuvant intraperitoneal cisplatin and fluorouracil and systemic fluorouracil chemotherapy in patients with resected gastric cancer

Purpose: This study was performed to assess the short- and long-term toxicities and the impact on relapse pattern and survival of postoperative intraperitoneal (IP) cisplatin and fluorourocil (FU) plus systemic intravenous (IV) FU as adjuvant therapy for gastric cancer patients who are at high risk for recurrence after potentially curative resection (T2N1-2MO or T3-4N_anyMO). Patients and Methods: Starting 14 to 28 days after potentially curative resection of primary gastric cancers, 35 patients were given IP cisplatin 25 mg/m² and FU 750 mg daily for 4 days; FU 750 mg/m² was concurrently given as a continuous 24-hour IV infusion. Five cycles of therapy delivered at 1 -month intervals were used. Results: After a median follow-up of 24 months, 51% of patients remain alive and free of disease. Sixteen patients have recurred; 13 of 16 had an intraabdominal component, whereas three had extraabdominal failure only. Two major treatment-related toxicities were noted: neutropenia and a late toxicity of peritoneal fibrosis (sclerosing encapsulating peritonitis [SEP]). There was one postoperative death. Eleven patients underwent second laparotomy: five patients had SEP, two patients had bowel obstruction from adhesions unrelated to SEP, and four patients had recurrent cancer. Potential causes of SEP included an alkaline pH of infused FU and cisplatin that possibly led to activation of cisplatin before infusion. Conclusion: IP cisplatin and FU and concurrent systemic FU is a tolerable adjuvant therapy in the postoperative setting for patients with resected gastric cancer. The recommended dosage schedule with this technique is cisplatin 25 mg/m² and FU 750 mg total dose IP with FU 500 mg/m² as a continuous 24-hour infusion daily for days 1 to 4. SEP as a late toxicity, which was observed in 15% of patients, is treatable by surgical lysis of adhesions.