Screening asymptomatic patients for colorectal lesions.

Purposes: To determine: 1) prevalence of significant colorectal lesions by demographics and risk factors; 2) frequency of 1 and 2 or more lesions by type, location, and size; 3) relation among villous component, location, and size of adenomas; and 4) frequency of nonsignificant lesions among patients with and without significant lesions.;

Method: One thousand asymptomatic patients, 45 years of age and older, with negative fecal occult blood tests, were screened using 60-cm flexible sigmoidoscopy and, if indicated, using colonoscopy.

Results: Thirty-six of the patients had 62 significant lesions (11 patients had 2 or more lesions). Fifty-four of the lesions were discovered by sigmoidoscopy in 1,000 patients, and 8 additional lesions were discovered in 5 of the 36 patients by colonoscopy. Lesions with villous components were more likely to be found in patients with 2 or more lesions (P = 0.0006). Smokers were more likely than nonsmokers to have significant lesions (P = 0.002). Among these patients, smoking and drinking were associated (P = 0.007). Males were more likely to have significant lesions than females (P = 0.006). Hemorrhoids, diverticulosis, and hyperplastic polyps were not associated with significant lesions.

Conclusions: The relationship between smoking and significant lesions provides further evidence that asymptomatic patients should stop smoking. Physicians should pay particular attention to men who smoke, even if they have negative occult blood tests.