Carcinoma located in a right-sided sigmoid colon: A case report.

Background: A right-sided sigmoid colon is an extremely rare anatomic variation that should be considered as a possibility by surgeons and radiologists before surgery. Here, we report the first clinical case of a carcinoma in a right-sided sigmoid colon revealed by a preoperative computed tomography (CT).

Case Summary: A 56-year-old Chinese man was admitted to the hospital with abdominal pain.