New technology called "virtual colonoscopy" is promising to offer fewer complications and be more cost-effective than the traditional colonoscopy.
Colonoscopies which are the most accurate test for colorectal cancer detection in current use, involve the insertion of a tube, or "endoscope," through the colon while the patient is sedated.
A small camera visualizes any polyps, which are then snared and removed for microscopic evaluation.
The researchers say by using computed tomography (CT) imaging of the colon, removing polyps smaller than 6 millimeters, which as a rule do little to reduce the risk of colorectal cancer, can be avoided along with the invasive and expensive colonoscopy procedure.
Lead researcher Dr. Perry J. Pickhardt, an associate professor in the school of medicine and public health and radiologist at the University of Wisconsin in Madison, says the almost nonexistent risk associated with such small polyps, means 90 percent of people do not need an invasive and expensive colonoscopy to screen for colon cancer.
Dr. Pickhardt says virtual colonoscopy is a very effective way to filter out these people and focus on those who really need the more invasive procedure.
Pickhardt says he is not suggesting that virtual colonoscopies replace traditional optical screening but non-invasive screening might increase the number of people who would then decide to undergo screening.
According to the American Cancer Society (ACS), colorectal cancers are the third most common cancers in the United States among both men and women and 112,000 Americans will be diagnosed with colon cancer this year; of those 52,000 will die.
At an increased risk for colon or rectal cancer are those over the age of 50, smokers, African-Americans, Jews of Eastern European descent, those with a personal or family history of the disease, or those with a history of polyps or bowel disease.
If caught early the disease as a rule responds well to treatment.
Virtual colonoscopy is a combination of sophisticated X-rays and CT scans of the abdomen after it has been pumped with air; from this a two and three-dimensional computer model of the gastrointestinal tract is generated, which reveals potential cancerous and precancerous lesions.
When dangerous lesions are identified, a second, more invasive procedure is then required.