Use of multidetector-row CT colonography for detection of colorectal neoplasia in patients referred via the Department of Health "2-Week-wait" initiative.
OBJECTIVE
Patients referred under the Department of Health 2-week wait initiative with symptoms of colorectal cancer frequently undergo whole-colon examination. We investigated the use of computed tomography (CT) colonography as an alternative to colonoscopy in this scenario.


METHODS
Fifty-four consecutive patients, referred via the 2-week wait initiative and scheduled for colonoscopy, consented to undergo multidetector CT colonography immediately before endoscopy. The site and morphology of any polyp or cancer detected by CT was noted and comparison made with subsequent colonoscopy.


RESULTS
Colonoscopy detected polyps or cancer in 29 patients (53.7%). CT colonography prospectively detected 18 of 41 (44%) polyps of 1-5 mm, three of four (75%) polyps of 6-9 mm, four of four (100%) polyps 10 mm or larger, and five of six (83%) cancers. The missed cancer occurred early in the series and was a perceptive error. The overall sensitivity, specificity, positive predictive value and negative predictive value of CT colonography for cancer and polyps 10 mm or greater on a per patient basis were 90, 100, 100 and 98%, respectively. CT detected one renal cancer and one colonic cancer, initially missed due to incomplete colonoscopy.


CONCLUSIONS
CT colonography is a robust technique for investigation of symptomatic patients. The learning curve must be overcome for optimal performance.
Department of Intestinal Imaging, St Mark's Hospital, Northwick Park, London, UK.
S A
SA
Taylor
S
S
Halligan
B P
BP
Saunders
S
S
Morley
C
C
Riesewyk
W
W
Atkin
C I
CI
Bartram
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000553:Ambulatory Care / Q000379:methods; D023881:Colonography, Computed Tomographic; D003113:Colonoscopy / Q000379:methods; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D007417:Intestinal Polyps / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity