[A case of recurrent early gastric cancer with peritonitis carcinomatosa successfully treated with TS-1].

A 62-year-old man with carcinomatous ascites more than 5 years after early gastric cancer operation was admitted to our hospital because of suspected pancreatic cancer, and was diagnosed with a relapse of the gastric cancer. TS-1 was administered at a dose of 120 mg/day. At the end of 1 course a partial response of a decrease of tumor markers and ascites and improvement of QOL was achieved, and the patient was followed in the outpatient clinic. The current case suggests that TS-1 may have a potent therapeutic efficacy in cases of gastric cancer relapse with carcinomatous ascites.