[Liver metastasis from sigmoid colon cancer with peritoneal dissemination showed a complete response to TS-1].

A 64-year-old man with unresectable sigmoid adenocarcinoma due to peritoneal dissemination (P3) and liver metastasis (H2) treated with TS-1, showed a complete response. TS-1 is an oral anticancer drug that produces biochemical modulation. It is composed of tegafur, gimestat and ostat potassium in a molar ratio of 1:0.4:1 to increase the effect of 5-FU and to decrease toxicity in the digestive canal. Treatment with TS-1 requires no hospitalization and can enhance the quality of life of the patient. TS-1 is expected to be an effective agent for the treatment of colon cancer with liver metastasis and peritoneal dissemination.