Medicare's 'No' on Virtual Colonoscopy Stirs Expert Debate
WEDNESDAY May 13, 2009 -- Medicare and Medicaid's decision Tuesday not to pay for a less invasive colon exam known as virtual colonoscopy has some experts applauding the move, while others claiming it could cost patients' lives.
Virtual colonoscopy, also known as CT colonography, is a procedure in which a detailed picture of the colon is created by an X-ray machine linked to a computer. Although the bowel must be prepped beforehand, it is much less invasive than standard colonoscopy, which usually involves sedation while a doctor examines the colon through an inserted scope and camera.
However, in a memo posted on its Web site Tuesday, the Centers for Medicare and Medicaid Services (CMS) said, "We have determined that there is insufficient evidence on the test characteristics and performance of screening CT colonography in Medicare-aged individuals, and that the evidence is not sufficient to conclude that screening CT colonography improves health benefits for asymptomatic, average-risk Medicare beneficiaries."
Supporters of the procedure weren't pleased by the move. Dr. J. Leonard Lichtenfeld, deputy chief medical officer for the American Cancer Society, believes that a less-invasive method such as virtual colonoscopy might encourage more Americans to get screened for colon cancer, the country's second-leading cancer killers.
"To say the least, I am personally very disappointed," Lichtenfeld wrote on his blog. "For me, the issue was reasonably straightforward -- we lose close to 50,000 people every year in this country from colorectal cancer. We could save thousands of lives if we were able to get people screened for this disease. The American Cancer Society believes that we should favor tests that prevent cancer, and has endorsed CT colonography as a reasonable test for this purpose."
Dr. Abraham Dachman, from the American College of Radiology's Colon Cancer Committee, concurred. "I think it's a bad decision," Dachman said. "I don't think it's in the best interests of our country. I think it's contrary to President Obama's stated emphasis on prevention and using new technology to benefit patients."
Dachman, who is also director of computed tomography at the University of Chicago Medical Center, noted that CT colonography is an effective screening tool and that Blue Cross and Blue Shield currently approve and pay for it.
CT colonography has been tested in older patients and found to be effective, Dachman added. So "to base a decision somewhat -- if not primarily -- on the fact that the cohort, and the effectiveness in that cohort, has not been studied is suspect, even for the layman," he said.
Other physicians agreed with the agency's move, but not always for the same reasons.
"I don't disagree with CMS's decision, but not because it doesn't visualize lesions in the colon," said Dr. Robert Fletcher, a professor of ambulatory care and prevention at Harvard Medical School. "The evidence that CT colonoscopy is accurate is quite strong. It's nearly as good as colonoscopy and much better than most of the other tests."
However, other aspects must also be considered, Fletcher said. He noted that if something suspicious does turn up on CT colonography, doctors must then go in and investigate it using traditional, invasive colonoscopy. In that scenario, patients would end up having to go through two difficult bowel-preparation regimens and two costly, uncomfortable procedures.
In a standard colonoscopy, polyps can be removed during the scoping procedure itself, Fletcher pointed out.
In addition, there is a concern about the dose of potentially harmful radiation received by the patient from the X-ray, Fletcher noted. Multiple CT colonographies would mean multiple doses of this radiation, he said.
"Most important, from my point of view, are the extra-colonic findings with CT colonoscopy. Findings you never set out to find, but nevertheless once you see them you have to go on to further evaluate them, which involves cost and risk, " he said.
That's because -- unlike standard colonoscopy -- CT colonoscopy doesn't only depict the colon, but the whole abdomen. It will show cysts and other growths in the liver and kidneys that can lead to further testing in many patients. "Those tests may often be futile and in any case may be dangerous and certainly are costly," Fletcher said.
In terms of expense, standard colonoscopies can cost up to $3,000, while CT colonography has a price tag of between $300 to $800.
Another expert agreed with Fletcher that perhaps CMS had acted wisely.
"I am pleased with the decision," said Dr. Douglas Rex, director of endoscopy at Indiana University Hospital in Indianapolis. "The Medicare population is definitely not the right population to begin the CT colonoscopy experiment in. I was pleased that the people at CMS had the courage to make the right decision."
Rex said that older patients do have a much higher prevalence of polyps, "so many more patients, if they are screened initially with CT colonoscopy, are going to need a colonoscopy in order to remove polyps."
He also seconded Fletcher's concern that virtual colonoscopy would pick up too many innocuous aberrations outside the colon. "Most of these are incidental and not important to the patient but result in tests that increase the cost and the risk to patients," he said.
Posted: May 2009