Case 18-1995

Presentation of Case A 59-year-old woman was admitted to the hospital because of increasing constipation, abdominal pain, and a rectosigmoid mass. The patient had been well until three months earlier, when pain in the right lower quadrant and constipation developed and gradually worsened; she passed mucus in her stools, without blood. Three weeks before admission colonoscopic examination at the gastrointestinal clinic showed a concentric mass, approximately 8 cm in diameter, in the sigmoid colon, with nearly complete obstruction. A pediatric endoscope was passed into the ascending colon with difficulty. No further abnormalities were observed. It was noted that the mucosa . . .