Can the localization of primary colonic tumors be improved by staging CT without specific bowel preparation compared to optical colonoscopy?
OBJECTIVE
To investigate the ability of staging computed tomography (CT) without bowel preparation to accurately localize colonic tumors compared to optical colonoscopy.


METHODS
The local institutional review board approved this retrospective and HIPAA-compliant study. Forty-six patients with colonic adenocarcinoma, preoperative colonoscopy, and staging CT within 60 days of resection were included. Patients underwent contrast enhanced CT imaging without bowel preparation or oral contrast. The colon was divided into four segments with the operative reports used as the standard. Rectal and cecal cancers were excluded. CT scans were reviewed by 5 readers in a segmental binary fashion using a 5-point confidence scale in two sessions blinded and unblinded to the colonoscopy report.


RESULTS
At surgery 49 tumors were found in 46 patients. Readers detected 86.1%, 74.3%, and 66.9% of lesions with 92.0%, 94.1%, and 95.4% accuracy for confidence scores of ≥ 3, ≥ 4, and 5. CT interobserver agreement was good (κ=0.82) for the unblinded and moderate (κ=0.60) for the blinded read. Colonoscopic localization was only 78.7% accurate with 2 tumors undiscovered. Colonoscopic accuracy was low in the descending colon (57.1%) and the transverse colon (55.6%).


CONCLUSIONS
Preoperative staging CT is more accurate than colonoscopy in the localization of colonic tumors.
Department of Radiology, Duke University Medical Center, DUMC 3808, Durham, NC 27710, USA.
Sebastian
S
Feuerlein
Lars J
LJ
Grimm
Matthew S
MS
Davenport
Clare M
CM
Haystead
Chad M
CM
Miller
Amy M
AM
Neville
Tracy A
TA
Jaffe
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003106:Colon / Q000000981:diagnostic imaging*; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D023881:Colonography, Computed Tomographic / Q000379:methods*; D003113:Colonoscopy / Q000379:methods*; D003287:Contrast Media; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D061848:Optical Imaging / Q000379:methods; D011856:Radiographic Image Enhancement / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
D003287:Contrast Media