Advanced sigmoid colon cancer with stenosis was discovered in a man in his 50's who presented with constipation. A radiological examination revealed peritoneal dissemination. Transverse colostomy was scheduled for the treatment of bowel obstruction. Multiple disseminated nodules were confirmed, and adenocarcinoma was detected from a nodule in the omentum. Eight courses of SOX plus bevacizumab caused the primary tumor to shrink and disseminated nodules to become radiologically undetectable. The patient underwent sigmoid colectomy 8 weeks after the last bevacizumab administration, and no disseminated nodules were found during the procedure. Histological assessment revealed no evidence of cancer cells in the colon and lymph nodes, and the histological effect was judged as Grade 3.