In 2006, 200,000 of them were performed in the United States. Overall, Americans have more than 14 million colonoscopies every year, and doctors agree doing more would save thousands of lives.
CBS News medical correspondent Dr. Jon LaPook reports the government's rejection of the latest high-tech approach was a big disappointment to many advocates of colon cancer prevention.
Dr. Otis W. Brawley, chief medical officer of the American Cancer Society says, "The American Cancer Society believes that virtual colonoscopy, or CT colonography, ought to be available as one of several options for colon cancer screening."
In a traditional colonoscopy, a fiberoptic instrument is used to examine the lining of the colon and remove polyps. In virtual colonoscopy, images of the colon are generated by a noninvasive body scan. Both have a similar detection rate for significant polyps; traditional colonoscopy usually costs at least twice as much.
The government maintains that, "The evidence is inadequate to conclude that CT colonography is an appropriate colorectal cancer screening test."
One concern is that costs would increase because polyps found by virtual colonoscopy require traditional colonoscopy to remove them. Advocates say reaching more people is worth the added expense.
"Right now about 40 percent of people over the age of 50 are getting any kind of screening for colon cancer," Brawley says. "We believe if virtual colonoscopy were more available, more people would be screened and more lives would be saved."
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