Large size, villous content and distal location are associated with severe dysplasia in colorectal adenomas

Adenomatous polyps are precursor lesions for colorectal carcinoma. The risk of cancer development has been associated with age and size, amount of villous component and high-grade dysplasia of adenomas. The subject-related and adenoma-related risk factors for severely dysplastic lesions were further investigated.

The study was performed in 474 men and 339 women undergoing endoscopic removal at index colonoscopy of 1217 polyps.

The male gender, cases aged over 55 and cases examined for rectal bleeding, showed an increased risk of colorectal polyps (odds ratios, OR = 1.95, 5.1 and 2.99, respectively). Adenomas synchronous with hyperplastic polyps of larger diameter (>10 mm) showed an increased risk of severe dysplasia (OR = 6.94). Severe dysplasia occurred more significantly in younger subjects harbouring villous growths (OR = 4.28, p < 0.03) and in larger adenomas (OR = 3.91, p < 0.001). The risk for severe dysplasia in relation to gender, age, multiplicity and location was higher in adenomas of larger diameter and with villous content. Multivariate analysis showed that distal site (p < 0.02), large size (p < 0.001) and villous content (p < 0.001) were the independent risk factors for severe dysplasia.

Large size, villous content and distal location are associated with severe dysplasia in colorectal adenomas. The risk for severe dysplasia does not appear to be correlated with age.