A case of recurrence of colon cancer with marked tumor reduction after effective chemotherapy is reported. The patient was a 27-years-old female who was admitted to the 1st department of surgery because of a giant abdominal tumor. She had undergone surgery for cecal cancer 16 months before admission. Abdominal and pelvic CT-SCAN revealed a giant tumor (21×18cm) invading the rectum and uterus. Surgical cannulation was performed into bilateral internal iliac arteries, and anti-cancer drugs (5-FU : 5000mg, ADR : 40mg, CDDP : 200mg) were administered intraarterially. The occurrence of hyperkalemia and striking rises in LDH, CEA, CA19-9 after the chemotherapy strongly suggested the tumor lysis syndrome, which to our knowledge, has not been reported as a complication of the treatment of colon carcinoma.