Is diverticulosis associated with colorectal neoplasia? A cross-sectional colonoscopic study.

OBJECTIVE

To determine the relationship between distal diverticulosis and risk for colorectal neoplasia.

METHODS

Patients undergoing first-time colonoscopy for any indication were eligible if they had no prior polypectomy, colonic resection, or inflammatory bowel disease. Patients completed a survey about risk factors for colorectal cancer (CRC) prior to colonoscopy. Endoscopists, blinded to study objective and survey results, recorded the size, extent (none, few, or many), and location of diverticuli and polyps.

RESULTS

The 502 participants were 67% male with a mean age of 58.6 yr. Twenty-three percent had extensive distal diverticulosis (EDD), 36% had > or =1 adenoma, and 14% had advanced neoplasia. Overall comparison of those with EDD versus few or no diverticuli revealed no differences in the risks of any neoplasia or advanced neoplasia, either distally (26.7%vs 25.4%; 12.9%vs 8.8%, respectively) or proximally (25%vs 18.4%; 6.0%vs 4.9%). Compared to women with few or no distal diverticuli, however, women with EDD were more likely to have any neoplasia and advanced neoplasia, both distally (34.6%vs 16.3%; p= 0.03, and 23.1%vs 5.7%; p= 0.003) and proximally (30.8%vs 14.9%; p= 0.049, and 11.5%vs 4.3%, p= 0.13). Adjustment for age did not affect results for advanced distal neoplasia (OR = 3.92; CI: 1.18-13); however, adjustment for the presence of a distal neoplasm eliminated the increased risk of proximal neoplasia associated with EDD (OR = 1.31; CI: 0.43-4.02).

CONCLUSION

In this study, women with EDD were more likely to have advanced distal neoplasia. The presence of distal neoplasia in women with EDD accounted for their increased risk of proximal neoplasia. Distal diverticulosis was not independently associated with proximal neoplasia in men or women.