BACKGROUND/AIMS: The purpose of this study is to evaluate the efficacy of CT colonography (CTC) in comparison with colonoscopy for the detection of colorectal adenomatous polyp in asymptomatic adults. METHODS: A total 208 asymptomatic adults underwent successive CTC and colonoscopy, on the same day. RESULTS: On the analysis of adenomatous polyps per subject, the sensitivity of CTC was 90% (9/10) in case of polyps > or =10 mm in size, and 67.7% (21/31) in case of polyps > or =6 mm in size. Those values of colonoscopy were 100% and 93.5%, respectively. The per-patient specificity of CTC was 98.0% (194/198) in case of polyps > or =10 mm in size and 88.1% (156/177) in case of polyps > or =6 mm in size. CTC missed 4 (3 flat adenomas and, 1 sessile adenoma) out of 17 adenomatous polyps > or =10 mm in size in 2 subjects. CONCLUSIONS: In asymptomatic adults, the sensitivity of CTC for detecting adenomatous polyps was lower than that of colonoscopy, particularly for the small lesions below 10 mm in size, and also for the flat adenomas > or = 10 mm in size. However, CTC showed a high sensitivity and specificity for detecting the subjects with clinically important colorectal adenomatous polyps > or = 10 mm in size. These results suggest that CTC has potential as a screening method for colorectal neoplasm.
Adenoma ; Adenomatous Polyps* ; Adult* ; Colonography, Computed Tomographic* ; Colonoscopy* ; Colorectal Neoplasms ; Humans ; Mass Screening ; Polyps ; Prospective Studies* ; Sensitivity and Specificity