How best to manage advanced esophageal cancer remains unresolved, especially in palliative care. Here, in a pilot study, we evaluated the efficacy and safety of concurrent chemoradiotherapy with S-1 and cisplatin in advanced esophageal cancer. Patients with locally advanced or metastatic squamous cell carcinoma of the esophagus received S-1 and cisplatin at doses of 70 mg/m(2)/day for 14 days and 70 mg/m(2) on day 1, respectively, every 3 weeks. Concurrently, radiotherapy was started at a dose of 200 cGy/day, up to a total of 5400 cGy. After concurrent chemoradiotherapy, additive chemotherapy was repeated up to six cycles. Thirty patients were enrolled in this study; of the 27 in whom efficacy could be evaluated, an objective response rate was seen in 20 (74.1%), including five (18.5%) complete pathologic responses in primary lesions. Improvement of dysphagia was seen in 21 (76%) patients. In patients with stage II or III esophageal cancer, the median progression-free survival and overall survival were 10.6 +/- 0.6 months (95% CI: 9.4-11.8) and 23.0 +/- 5.1 months (95% CI: 13.0-32.9), respectively. In patients with stage IV esophageal cancer, the median progression-free survival and overall survival were 5.4 +/- 1.6 months (95% CI: 2.2-8.6) and 11.6 +/- 1.6 months (95% CI: 8.4-14.8), respectively. The main hematological toxicity was neutropenia, but no neutropenic fever was observed. The major non-hematological toxicities were asthenia and vomiting, mostly of grades 1 and 2. Thus, concurrent chemoradiotherapy with S-1 and cisplatin may be a promising nonsurgical treatment in advanced esophageal cancer.