Chronic diverticulitis vs. colorectal cancer: findings on CT colonography.

PURPOSE: The purpose of this update article is to evaluate findings on CT colonography in patients with chronic diverticulitis and to compare the findings in patients with colorectal carcinoma.
MATERIALS AND METHODS: Different morphological criteria retrieved from a literature review were retrospectively analyzed in a series of 13 patients with proven chronic diverticulitis. The findings were compared with a series of 10 patients with colorectal carcinoma.
RESULTS: Overall, the findings in chronic diverticulitis resemble the findings in acute diverticulitis. The advantage of virtual CT colonography in differentiating both entities relies in the combination of morphological features previously described on axial computed tomography and double contrast barium enema. The single strongest morphological feature pointing towards the diagnosis of chronic diverticulitis is the presence of diverticula in the affected segment. In the presence of diverticula in the affected segment, a long segment (≥10 cm), thick fascia sign without adenopathies, mild bowel wall thickening, tapered margins, and distorted but preserved mucosal folds are likely to further improve accuracy of diagnosing chronic diverticulitis.
CONCLUSION: The single strongest morphological sign to differentiate chronic diverticulitis from colorectal cancer is the presence of diverticula in the affected segment.