Sigmoid stenosis caused by diverticulosis mimicking advanced colorectal cancer.

Stenosis is a rare complication of acute diverticulitis, difficult to differentiate from colon cancer. We present a 63-year-old woman with right lumbar pain radiating to the back. A sigmoid stenosis was detected by magnetic resonance imaging. Three biopsies were performed, all of which were negative for malignancy. From CT images with data of circumferentially thickened intestinal wall along 6 cm, stenosing the lumen enlarged regional lymph nodes. A sigmoid resection was performed and the results of histological examination showed complicated diverticulitis of the large intestine with exacerbation, abscending and spread of the inflammatory process with involvement of the pericolic tissues. Given the high risk of developing a malignant process in patients with acute diverticulitis and the slightest doubt should be followed by surgical treatment.