Detection of colorectal lesions with virtual computed tomographic colonography

doi:10.1016/S0002-9610(01)00857-1

The American Journal of Surgery

Volume 183, Issue 2, February 2002, Pages 124-131

https://doi.org/10.1016/S0002-9610(01)00857-1 Get rights and content

Abstract

Background: The aim of our study was to compare the performance of virtual computed tomographic colonography with that of conventional colonoscopy in a blinded, prospective study in 165 patients with suspected colorectal lesions.

Methods: There were 165 patients, all referred for conventional colonoscopy, who underwent preliminary virtual computed tomographic colonography. Computed tomograhic images of all suspected lesions were analyzed and subsequently compared with conventional colonoscopy findings.

Results: There were 30 colorectal cancers and 37 polyps identified at conventional colonoscopy. Virtual computed tomographic colonography correctly detected all cancers, as well as 11 of 12 polyps of 10 mm in diameter or larger (sensitivity, 92%); 14 of 17 polyps between 6 and 9 mm (sensitivity, 82%); and 4 of 8 polyps of 5 mm or smaller (sensitivity, 50%). The per-patient sensitivity and specificity were 92% and 97%, respectively.

Conclusions: Virtual computed tomographic colonography has a diagnostic sensitivity similar to that of conventional colonoscopy for the detection of colorectal lesions larger than 6 mm in diameter.

Section snippets

Patient population

There were 165 consecutive patients (79 men and 86 women; mean age, 62 years; age range, 26 to 84 years), all referred for conventional colonoscopy, who underwent preliminary virtual computed tomographic colonography.

Criteria for inclusion were: positive fecal occult blood test (51 patients, 31%); altered bowel habits (40 patients, 24%); history of colorectal cancer resection (37 patients, 22%); rectal bleeding (25 patients, 15%); anemia of unknown origin (7 patients, 4%); and history of polyps

Conventional colonoscopy

Conventional colonoscopy showed normal findings in 113 patients (68%) and abnormal findings in 52 patients (32%). A total of 30 colorectal cancers and 37 polyps were detected. Conventional colonoscopy was not completed in nine cases (6% of all examinations) due to the presence of occlusive neoplasms. The average duration of the procedure was 25 min and no complications were observed.

Colorectal cancers were located in the rectum (n = 5), sigmoid colon (n = 13), descending colon (n = 1),

Comments

It is widely accepted that most colorectal cancers develop from preexisting adenomatous polyps [13]. Prompt diagnosis and treatment of these precursor adenomas are therefore essential to reduce the incidence and the mortality of colorectal cancers [13], [16], [17], [18]. As pointed out above, several different screening methods are currently available, but none of them can be considered flawless in terms of diagnostic accuracy, patient tolerance, and safety. At present, in our opinion, there is

Acknowledgements

Supported in part by Mallinckrodt Research Grant ECR Research and Education Fund.

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Scientific paperDetection of colorectal lesions with virtual computed tomographic colonography

Abstract

Section snippets

Patient population

Conventional colonoscopy

Comments

Acknowledgements

Gastroenterology

Gastroenterology

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Scientific paper
Detection of colorectal lesions with virtual computed tomographic colonography