Colonoscopy utilizes direct visualization of the entire colon to detect pre-cancerous growths, including smaller polyps, even below 1 cm. This test allows removal of suspicious polyps without surgery at the time of the exam. Three studies have shown that colonoscopy prevents about 80 percent of colorectal cancers from developing by removing pre-cancerous polyps. Colorectal cancer screening's effect on early detection and prevention through polypectomy has been identified as a main contributing factor for the declining rates of colorectal cancer incidence and deaths from the disease.
About CT Colonography
CT colonography technology requires the same cathartic bowel preparation and restricted diet as colonoscopy. The test requires insertion of a tube in the rectum and insufflation of the abdomen with air or gas while patients are awake. It does not provide the opportunity to remove polyps or suspicious lesions. There are unresolved questions about radiation risks and identifying small or flat polyps. CT colonography may be useful for those who refuse, who cannot undergo, or who have failed prior colonoscopy.
The Need to Follow-up Suspicious Findings
The management of any findings from stool tests, barium enema exams, or CT colonography is an important part of a screening program using these tests:
-- For any of the stool tests, a positive finding will require a follow-up colonoscopy.
-- For flexible sigmoidoscopy, patients who have adenomas discovered at
sigmoidoscopy should undergo colonoscopy, based on evidence suggesting that
patients who have an adenoma of any size in the distal colon (visible
during the exam which only views part of the colon) are at increased risk
for advanced neoplasia proximally (higher up in the colon beyond the reach
of the sigmoidoscope.)
|SOURCE American College of Gastroenterology|
Copyright©2008 PR Newswire.
All rights reserved