['There is limited data assessing the relationship between cholecystectomy and colorectal adenomatous polyps (AP). Our aim was to determine if cholecystectomy was associated with an increased prevalence of advanced AP in male veterans.', 'The relationship of whether prior cholecystectomy modified the natural history of AP was investigated in a retrospective study. The patients were divided into two groups: 1) those with AP and a history of cholecystectomy, and 2) those with AP, but without a history of cholecystectomy. Factors in each group associated with advanced AP were examined by univariate analysis (UA) and stepwise logistic regression analysis to determine independent predictors of aggressive clinical characteristics of polyps. Statistical significance was determined at a P < or = 0.05.', 'We identified a total of 1234 patients with AP (cases = 127, controls = 1107). The mean age of patients was 64.1 +/- 1.9 (standard deviation) years. By UA, those with a prior cholecystectomy had a greater mean number of AP (4.2 vs. 3.5; P = 0.04) and more advanced polyps (P = 0.037) than those without a cholecystectomy. By logistic regression, prior cholecystectomy was associated with more advanced AP (OR = 1.5 [1.0-2.2]; P = 0.04). Patients who had a cholecystectomy were 51% more likely to have advanced AP. There appeared to be a trend towards increased time from cholecystectomy being associated with advanced polyps (9.69 years vs. 8.99 years, P = 0.056).'] Does a previous cholecystectomy increase the risk of developing advanced adenomas of the colon?