Colorectal neoplasia: performance characteristics of CT colonography for detection in 300 patients.
OBJECTIVE
To determine the sensitivity and specificity of computed tomographic (CT) colonography for colorectal polyp and cancer detection by using colonoscopy as the reference standard.


METHODS
Three hundred patients underwent CT colonography followed by standard colonoscopy. Bowel preparation consisted of magnesium citrate and polyethylene glycol. After colonic air insufflation, patients underwent scanning in the supine and prone positions with 3-mm collimation during a single breath hold. The transverse CT images, sagittal and coronal reformations, and three-dimensional endoluminal images were interpreted by two radiologists independently, and then a consensus reading was performed. CT colonographic findings were correlated with standard colonoscopic and histologic findings.


RESULTS
The overall sensitivity and specificity of CT colonography for polyp detection were 90.1% (164 of 182) and 72.0% (85 of 118), respectively. By using direct polyp matching, the overall sensitivity was 69.7% (365 of 524). The sensitivity was 90% (74 of 82) for the detection of polyps 10 mm or larger, 80.1% (113 of 141) for polyps 5.0-9.9 mm, and 59.1% (178 of 301) for polyps smaller than 5 mm. The sensitivity was 94% (64 of 68) for the detection of adenomas 10 mm or larger, 82% (72 of 88) for adenomas 5.0-9.9 mm, and 66.9% (95 of 142) for adenomas smaller than 5 mm. CT colonography was used to identify all eight carcinomas.


CONCLUSIONS
CT colonography has excellent sensitivity for the detection of clinically important colorectal polyps and cancer.
Yee
J
J
Department of Radiology, Veterans Affairs Medical Center, 4150 Clement St, San Francisco, CA 94121, USA. judy.yee@radiology.ucsf.edu
Akerkar
G A
GA
Hung
R K
RK
Steinauer-Gebauer
A M
AM
Wall
S D
SD
McQuaid
K R
KR
D018256:Adenomatous Polyps / Q000000981:diagnostic imaging / Q000453:epidemiology; D016022:Case-Control Studies; D003111:Colonic Polyps / Q000000981:diagnostic imaging / Q000453:epidemiology; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed