We read with interest paper by Graser et al1 comparing CT colonography (CTC) with optical colonoscopy (OC) and other screening tests in an average-risk population. In a series of 311 subjects, the authors described 13 cases of advanced neoplasia (high-grade dysplasia or a villous component) in <10 mm polyps. In detail, seven of these cases occurred in <5 mm adenomas, so that diminutive adenomas accounted for 16% of all of the advanced neoplasia detected in the study, also being more frequent than 6–9 mm advanced adenomas. Such a relatively high rate of advanced neoplasia in <5 …