[A case of pathologically complete response in a patient with locally advanced sigmoid colon cancer after chemotherapy including bevacizumab/FOLFOX4].

: A 65-year-old man complaining of abdominal pain was admitted to our hospital. A diagnosis of colon ileus due to sigmoidal colon cancer was made. A stoma was created at the transverse colon, and elective surgery was scheduled. During the operation, the tumor was found to have invaded the bladder and the pelvic wall, making curative resection impossible. Chemotherapy consisting of bevacizumab/oxaliplatin, Leucovorin, and 5-fluorouracil(FOLFOX4, intravenous drip infusion every 2 weeks)was started. After 12 courses of treatment, remarkable shrinkage of the tumor was noted, which led us to perform a sigmoidectomy and partial resection of the bladder wall. A histopathological study of the surgically resected specimen showed no cancer cells. Recovery was uneventful and the patient was discharged on the 17th postoperative day. In cases of advanced colon cancer, complete response of the primary tumor with preoperative chemotherapy is very unusual. We conclude that chemotherapy with bevacizumab/FOLFOX4 plays a role in the management of advanced/unresectable colon cancer.