March 2013

CT Colonography’s Slow Progress
By Robert J. Murphy
Radiology Today
Vol. 14 No. 3 P. 26

Virtual colonoscopy appears to be moving toward approval for Medicare reimbursement, but advocates don’t expect that to happen before 2015.

First developed in 1994, CT colonography (CTC) has yet to be approved for Medicare reimbursement. A Centers for Medicare & Medicaid Services (CMS) panel in 2009 denied reimbursement approval for CTC (also known as virtual colonoscopy) for three reasons: a lack of data pertaining to risks associated with the procedure’s radiation dose, its performance in people of Medicare age, and extracolonic findings requiring further workup. Meanwhile, a growing number of commercial payers already have approved reimbursement for the procedure.

CTC proponents, including ACR representatives, returned to the CMS in 2012 with data addressing those three concerns. The procedure’s radiation dose, progressively lowered over the years, was found to be nonthreatening; it has been proven effective in older adults; and extracolonic findings were rare enough to make them a nonissue.

“We presented to them the new peer-reviewed publications that had come out since March 2009, and we were very well received,” says Judy Yee, MD, a professor and the vice chair of radiology at the University of California, San Francisco; the chief of radiology at the San Francisco VA Medical Center; and the head of the ACR’s Colon Cancer Committee. “We asked them whether there was any other evidence gap that they could see, and they said no.”

However, despite the positive reception from the CMS, hurdles remained. CTC advocates in July 2012 presented their case to the US Preventive Services Task Force (USPSTF), a Medicare advisory body that, among other tasks, develops guidelines for colorectal cancer screening, and requested expedited review.

“We just heard back from them [in January 2013] that they will consider colorectal cancer screening earlier,” Yee says. “It will come up on their agenda in the latter half of 2013. It’s all evidence based, and it will take them at least 18 months to complete a review and then come up with their recommendation.”

Assuming the USPSTF assigns a passing score, presumably the earliest to expect Medicare approval of CTC is mid-2015.

Inadequate Screening Rates
The low rate of colorectal cancer screening, usually estimated as less than 50% of the eligible population, was the impetus for pursuing Medicare reimbursement for CTC. The American Cancer Society’s guidelines recommend that anyone aged 50 and older be screened for colorectal cancer. The frequency hinges on the type of screening test: optical colonoscopy, every 10 years; CTC, every five years; ethmoid sigmoidoscopy, every five years; and fecal blood test, annually.

“CTC and colonoscopy are considered the two best options,” said Kenji Suzuki, MD, an assistant professor of radiology and a member of the Medical Physics and Cancer Research Center at the University of Chicago, in an e-mail interview. “They have the highest sensitivity for detection of polyps among the four options. Studies found that patients who took both [tests] prefer CTC to colonoscopy because of its minimal invasiveness, greater comfort, and shorter exam time.”

While studies show CTC’s clinical effectiveness in detecting preadenomal polyps measuring 6 mm or greater—along with general patient preference—overall colorectal screening rates have remained fairly flat in recent years.

“The growth of virtual colonoscopy has been inhibited by two related factors,” says Mark J. Baumel, MD, founder and president of Delaware-based Colon Health Centers of America, which establishes clinics offering both CTC and optical colonoscopy. “No. 1, the lack of Medicare coverage. No. 2, the shadow that the lack of coverage casts in the environment. There are patients and doctors who come to the conclusion that if Medicare isn’t covering this, there must be something wrong with it.”

This is no small matter given that colorectal cancer ranks third for cancer fatalities, behind lung and prostate cancers for men, and lung and breast cancers for women. Colorectal cancer largely is preventable through proper screening. Its proponents believe that makes it all the more regrettable that Medicare still denies CTC reimbursement except for diagnostic procedures and in cases of failed optical colonoscopy. It’s worth noting that President Obama, now aged 51, opted to receive CTC rather than an optical colonoscopy as part of his annual physical.

“What we’re trying to do is to get about 40% to 50% of patients off the screening sidelines,” Baumel says. “We think that’s the main focus for virtual colonoscopy. I think one of the problems with the [2009] Medicare review of virtual colonoscopy is that although they compared it favorably with traditional colonoscopy, they failed to recognize that traditional colonoscopy [which Medicare reimburses] is only hitting about 50% of people. It should be more of an issue of ‘here is another great technology that yields a higher percentage of people screened, so let’s get more people screened.’”

Meanwhile, a growing number of commercial payers, including CIGNA, United Healthcare, and many regional Blue Cross/Blue Shield plans, recognize CTC’s clinical value and reimburse for the procedure in 30 states. No one doubts, however, that Medicare’s approval of CTC would increase overall screening rates.

There’s also the cost factor. A ballpark cost range for optical colonoscopy is $1,500 to $2,000, while CTC costs roughly $500 to $1,000.

Turf Battle?
As CTC proved successful in clinical studies, a perceived threat to their practice arose among some gastroenterologists. Optical colonoscopy represents a fairly large segment of the typical gastroenterology practice—and a much smaller piece of a radiologist’s work. It stands to reason that expanded use of CTC might reduce the demand for optical colonoscopy and therefore sharply cut a gastroenterology practice’s bottom line.

Baumel says this is a false premise “because, in reality, gastroenterologists don’t have anything to worry about. What we see is colonoscopy numbers continuing to go up. Even as virtual colonoscopies are adopted in certain areas, gastroenterologists feared it would cut into their numbers because quick screening is their bread and butter. Now for radiologists, on the other hand, virtual colonoscopies will just be an increased slice of business. So radiologists are not going to the mat fighting this. It’s not worth their effort.”

What about a supposed turf battle over this issue between radiologists advocating CTC and gastroenterologists who were presumed to have much to lose if CTC becomes Medicare-reimbursed? The latter fear may well be overblown. At the professional-association level, radiologists actually have an ally, not a foe, among organized gastroenterologists. The alliance can help promote greater numbers of colorectal screenings. This could render the possibility of a turf battle moot. If that’s the case, arguably the so-called turf battle between radiologists and GIs counts more as a mirage than hard-core reality.

 “When we met [in 2012] with CMS and USPSTF, we had gastroenterologists with us from the American Gastroenterological Association,” Yee says. “They’re supportive of CTC. They want it reimbursed as well. We want to bring in additional patients to be screened for colon cancer who never would have come in the first place.”

Working Together
Physicians in the gastroenterology and radiology departments at the University of Wisconsin-Madison have offered both CTC and optical colonoscopy to eligible patients since 2004 with success. The university’s patient-flow model—replicated at the Colon Health Centers of America, among other sites—offers patients a choice between the two procedures. Those opting for CTC then have the opportunity of receiving an optical colonoscopy at the same time if the CTC reveals potentially precancerous polyps. The advantage is that patients can avoid a second bowel-cleansing preparation and a return visit.

Seven years after instituting the dual-testing paradigm, the university’s academic clinicians have an illuminating, if not counterintuitive, story to tell. “Since the initiation of CTC screening at our institution, the overall number of total colorectal cancer screening examinations (CTC + colonoscopy) has greatly increased,” according to a 2012 paper authored by University of Wisconsin researchers. “The initiation of a CTC screening program did not lead to a reduction in the number of colonoscopic examinations performed. Conversely, a significant increase in the number of screening tests and total colonoscopies completed was observed.”

“CTC utilization has increased sharply in Europe, primarily as a diagnostic test, as even colonoscopy screening is low-volume there,” said Perry Pickhardt, MD, chief of gastrointestinal imaging in the department of radiology at the University of Wisconsin and a well-known researcher concerning CTC, in an e-mail interview. “Growth has been steady but slower in the US, largely due to lack of widespread coverage for CTC screening. At the University of Wisconsin, we’ve enjoyed widespread local coverage for CTC screening since 2004. There has been an increase in diagnostic CTC for Medicare, but the numbers are still small relative to optical colonoscopy. Nonetheless, the test is surely but slowly being recognized for the excellent screening tool that it is but not fast enough. However, our GI docs no longer fear it as much, as they see how complementary it is, plus it hasn’t really affected their volumes.”

Minimizing CTC Prep
Researchers continue looking for ways to ease patient preparation for colonoscopy, as it’s been long suspected that the low screening rates, including for CTC, are largely attributable to the bowel-cleansing preparation that patients view with trepidation. To make CTC more tolerable for eligible screening candidates, researchers and clinicians recently have developed minimal (noncathartic) preparation methods.

“The major advantage of a laxative-free approach is the potential for an overall increase in screening compliance, particularly from those seeking to avoid cathartic preparation,” Pickhardt wrote in a 2007 Mayo Clinics Proceedings editorial. Noncathartic preparation “is the future of CTC,” according to Suzuki.

Expanding CTC also involves training radiologists to read exams. “One issue on the hospital side is a long learning curve of radiologists in reading CTC,” Suzuki said. “Not all radiologists can read CTC.”

Computer-assisted detection software designed to help physicians interpret CTC findings may shorten that learning curve. In addition, numerous training programs have been established to educate clinicians in the subtleties of performing and reading CTC exams.

“It’s making sure that radiologists are well trained to perform the technique, like with anything else that’s new, “ Yee says. “I think continuing education is a necessary part of every field, in particular learning something like CTC. You have to have additional focused training in the area.”

Finally, there’s the matter of educating patients about the benefits and effectiveness of CTC as well as the fact that commercial insurers increasingly are covering the procedure. If CTC is approved for Medicare reimbursement in 2015, that may become a nonissue, but until then, it remains a significant obstacle to widespread patient and physician acceptance.

— Robert J. Murphy is a freelance medical writer based in Philadelphia.