Volvulus of the Sigmoid Colon Associated With Rectal Cancer: A Case Report

Sigmoid volvulus is one of the three most common causes of acute colonic obstruction. Predisposing factors include chronic constipation, adhesion from a prior abdominal surgery, and megacolon. However, concomitant presentation of volvulus of the sigmoid colon and rectal cancer is extremely rare. We report a case of a 50-year-old woman with coexisting volvulus of the sigmoid colon and rectal cancer. The patient presented with abdominal distension and pain for 2 days. On computed tomography, the whole colon was dilated with gas and feces. A whirl sign with rotation of the inferior mesenteric vessel was identified.