Diverticular disease as a risk factor for sigmoid colon adenomas

Diverticular disease and colorectal neoplasia share similar epidemiological features and risk factors.

To evaluate a possible association between diverticular disease and both adenomas and colorectal cancer in patients undergoing total colonoscopy.

Overall, 630 consecutive patients were recruited from the 3 Units. Inclusion criteria were age over 45 years and the performance of total colonoscopy. Demographic and clinical data were recorded. Adenomas were defined as advanced when their size was >1 cm in diameter, and/or the percentage of the villous component was >30% and/or high grade dysplasia was present.

At endoscopy, 291 (47%) out of 630 patients presented evidence of diverticular disease. Adenomas were found in 92 (31.9%) patients with diverticular disease and in 98 (28.9%) patients without [p=ns]. The prevalence of adenomas located in the sigmoid colon was significantly higher in patients with diverticula than in controls (64.1% vs 41.8%; p<0.05). Similarly, the detection of advanced adenomas located in the sigmoid colon was more likely in patients with diverticula than in controls (59.6% vs 37.5%; p<0.05). Colorectal cancer prevalence was similar in patients with and without diverticula (8.3% vs 7.1%; p=ns), and no difference was detected regarding site, between the two groups.

Patients with diverticular disease have a higher risk of harbouring adenomas and advanced adenomas in the sigmoid colon. This observation should be taken into account in screening and surveillance programmes for colorectal neoplasia.