Abstract
We evaluated the accuracy of primary colorectal cancer screening using CT colonography (CTC). The subjects consisted of 1,209 examinees who underwent primary colorectal cancer screening using CTC between July 2009 and November 2011. Close examination was required in 60 subjects. Based on the results of close examination in these subjects, the detection ability of CTC according to the location, size, and gross type of the lesion were evaluated. The sensitivity according to the location of the lesion was 92.9% in the ascending colon, 86.7% in the transverse colon, 66.7% in the descending colon, 100% in the sigmoid colon, and 100% in the rectum. The sensitivity according to the size of the lesion was 85.3% for 6-9 mm, 100% for 10-19 mm, and 100% for ≥ 20 mm. The sensitivity according to the gross type was 93.8% for the sessile type (I s), 100% for the semipedunculated type (I sp), 100% for the pedunculated type (I p), and 40.0% for the superficial elevated type (II a). Colorectal cancer was detected in 3 subjects (M cancer in 2 patients and SM cancer in 1 patient). The cancer detection rate was 0.25%. Colorectal cancer screening using CTC may be a useful new colorectal cancer screening method.
