Laxative-free virtual colonoscopy can detect large polyps

Share this article:

Computed tomographic (CT) colonography performed on persons who did not undergo laxative-induced bowel cleansing before the screening test accurately detected adenomas 10 mm or larger. However, the test was less accurate for smaller lesions among these patients.

The American Cancer Society has approved CT colonography, or virtual colonography, as a valid screening test for colorectal cancer. Although this method uses a CT scanner to screen for colon cancer and polyps noninvasively, patients are still required to take a bowel-cleansing laxative before the procedure, as is the case for standard optical colonoscopy. The laxative bowel preparation prevents some people from participating in screening, noted Judy Yee, MD, chief of radiology at the San Francisco (California) VA Medical Center and professor and vice chair of radiology at University of California, San Francisco, and coinvestigators in their report for Annals of Internal Medicine (2012;156[10]:692-702). The team sought to assess the performance of laxative-free, CT colonography in detecting adenomas 6 mm or larger, as well as the patient experience.

The prospective test comparison of laxative-free CT colonography and optical colonoscopy involved 605 adults, aged 50 to 85 years, who were at average to moderate risk for colon cancer. The study revealed the following:

  • For adenomas 10 mm or larger, per-patient sensitivity and specificity for CT colonography was 91% and 85%, respectively, vs 95% and 89%, respectively, for optical colonoscopy—statistically insignificant differences.
  • For adenomas 8 mm or larger, sensitivity of CT colonography was 70%, vs 88% for optical colonoscopy.
  • For adenomas 6 mm or larger, sensitivity of CT colonography was 59%, vs 76% for optical colonoscopy.
  • Specificity for optical colonoscopy was greater than that for CT colonography for adenomas 8 mm (91% vs 86%) and for adenomas 6 mm or larger (94% vs. 88%).
  • Patient's reported more comfort and less difficulty of examination preparation with CT colonography than with optical colonoscopy.

The researchers concluded that these results suggest a possible role for laxative-free CT colonography, which is still in the early stages of development, as an alternative screening method.

Share this article:
You must be a registered member of ONA to post a comment.

Sign Up for Free e-newsletters

Regimen and Drug Listings

GET FULL LISTINGS OF TREATMENT Regimens and Drug INFORMATION

Bone Cancer Regimens Drugs
Brain Cancer Regimens Drugs
Breast Cancer Regimens Drugs
Endocrine Cancer Regimens Drugs
Gastrointestinal Cancer Regimens Drugs
Genitourinary Cancer Regimens Drugs
Gynecologic Cancer Regimens Drugs
Head and Neck Cancer Regimens Drugs
Hematologic Cancer Regimens Drugs
Lung Cancer Regimens Drugs
Other Cancers Regimens
Rare Cancers Regimens
Skin Cancer Regimens Drugs

More in Web Exclusives

Upgraded Prostate Cancer Risk Calculator 2.0, with emojis, is available online

A calculator to help men and their doctors assess the risk of prostate cancer has had a major upgrade to enhance men's and their physicians' understanding of a man's risk of prostate cancer.

Mutations in a gene essential for cell regulation cause kidney cancer in ...

Mutations in a gene that helps regulate when genes are switched on and off in cells have been found to cause rare cases of Wilms tumor, the most common kidney cancer occurring in children.

Lung cancer rates declining but vary by subtype, sex, race/ethnicity, and age

A new analysis confirms that US lung cancer rates are declining overall, but it also uncovers previously unrecognized trends related to cancer subtype, sex, race/ethnicity, and age.