Abstract
A 64-year-old man was presented with abdominal distension and poor appetite was diagnosed as having colonic obstruction associated with anatomical anomaly of the intestine by close exploration. An expandable metallic stent was placed under colonoscopy. A tumor completely encircling the sigmoid colon was found. It was histologically diagnosed as well differentiated adenocarcinoma. A CT angiography identified that the inferior mesenteric artery (IMA) had branched from the median of the abdominal aorta and pursued the bilateral symmetry course against the usual run. Laparoscopic resection was electively performed. During the surgery, another tumor was detected at the terminal ileum. Ileocecal excision was added and the pathology showed the tumor to be primary cancer of the small bowel.
Sometimes we encounter case reports on gastrointestinal cancer associated with intestinal malrotation. However, our case is extremely rare in terms of its anatomical characteristics that the IMA pursued the bilateral symmetry course and the colon from the descending to the sigmoid colon was located in the right side of the abdomen, as well as of synchronous double cancer involving the sigmoid colon and the small bowel. We thus present our case.
