The aim of this study was to determine the risk of polyps < 6 and between 6 and 10 mm in terms of progression to malignancy and to evaluate the influence of age, gender, and colonic localization on malignancy development. Thirteen hundred sixty-nine polyps < 10 mm identified in 680 patients were retrospectively evaluated. Sixty-seven and two-tenths percent of polyps < 10 mm were of a neoplastic nature. The incidence of neoplasia was higher in left-sided and small polyps than diminutive polyps. In patients older than 60 years, small polyps showed a higher rate of high-risk histology than diminutive polyps, while the same relationship did not exist in other age groups. In male patients over 60 years of age, the rate of high-risk histology was higher in small polyps than in diminutive polyps.