A pilot study of combination chemotherapy with S-1 and low-dose cisplatin for highly advanced gastric cancer

Background: The surgical outcome for advanced gastric cancer, even following curative surgery, is associated with a poor prognosis. A pilot study in advanced gastric cancer patients was carried out using pre-operative chemotherapy with S-1 and low-dose cisplatin (CDDP) (TSLD). Patients and Methods: Twenty-one patients with stage IV gastric cancer were treated with TSLD as the initial treatment, after informed consent had been obtained. Surgery was performed when curative resection was deemed feasible in selected patients who showed improvement in their tumors. Other regimens including CPT-11 or taxanes were utilized as second-line chemotherapy when the tumor showed no change or progressive disease following TSLD therapy. Results: No patient had a complete response, while 11 had partial responses following TSLD therapy, yielding an overall response rate of 52.4%. Fifteen out of 21 (71.4%) underwent surgery following TSLD therapy, while curative surgery determined by histological investigation was performed in 10 out of 15 (47.6%) patients. No grade 4 toxicities or treatment-related deaths were observed. The following grade 3 toxicities were observed: neutropenia (6 patients), thrombocytopenia (1 patient) and anemia (1 patient). The other toxicities observed, including gastrointestinal toxicity, were grade 2 or less. The median survival time of all patients was 526 days, and 1- and 2-year survival rates were 64.9% and 41.7%, respectively. Conclusion: TSLD is a potent regimen with a low toxicity profile for highly advanced gastric cancer.