[A Case of Advanced Sigmoid Colon Cancer That Was Resected after Chemoradiation Therapy Following Ineffective Chemotherapy].

We report a case of advanced sigmoid colon cancer that was resected after chemoradiation therapy(CRT)following ineffective chemotherapy. A 59-year-old woman harbored a lower abdominal tumor the size of an infant's head and was diagnosed with a huge sigmoid colon cancer with invasion to the urinary bladder and metastases to the para-aortic lymph nodes. The patient received 2 courses of modified FOLFOX6(mFOLFOX6)plus cetuximab therapy, which was assessed as ineffective; She then received CRTwith 50.4 Gy in 28 fractions plus concurrent oral S-1(100mg/day for 28 days). Tumor shrinkage in the primary lesion was achieved after CRT; total pelvic exenteration with the removal of metastatic para-aortic lymph nodes was then performed 5 months after the first diagnosis. This case of locally distant advanced colon cancer in the pelvic cavity coexisting with resectable metastatic lesions suggested that CRTmight contribute to successful local treatment after the failure of preoperative chemotherapy.