Medical Device Daily National Editor

The virtual colonoscopy sector appears to be on the verge of taking two fairly large steps backward, at least in the near term.

The Centers for Medicare & Medicaid Services last week unveiled its determination, described as "tentative," to end reimbursement coverage of virtual colonoscopies, also known as virtual colonography (Medical Device Daily, Feb. 13, 2009). And the current economic downturn obviously will shrink the number of discretionary dollars to pay out of pocket for this scanning modality, one that the federal government clearly has placed under a "dubious efficacy" type of cloud.

While the agency will offer the pro forma, 30-day opportunity for public input potentially capable of altering its stated intent, reversal of the tentative decision seems highly unlikely, based on the plethora of arguments offered in its posted web document.

The agency's rationales for supporting non-reimbursement of the CT type of colon scanning, called CTCs, are multiple: lack of clinical evidence indicating that the virtual method is able to detect small polyps as frequently as standard colonoscopies, those polyps potentially becoming cancerous; the necessity to follow a finding of polyps via CTC screening with diagnosis by standard colonoscopy; the risks of downstream cancer offered by the X-ray radiation used to acquire a virtual scan via CT; and overall failure of benefit in a cost-effectiveness analysis.

Perhaps the most pointed comment by the agency was that it simply had failed to find enough evidence to support the claim that CTCs improved outcomes for Medicare beneficiaries.

And it also downplayed one of the major arguments that the virtual colonography sector has offered as a key benefit for this modality — that because the exam offers much less discomfort to those screened, more people are likely to have it done, thus reducing the rate of colon cancer fatalities.

The agency statement notes also what the CTC sector may tend to leave out of its procedural descriptions: that the same day-before bowl cleansing (technically, "purgatory bowel preparation") is "similar" to that for standard colonoscopy, which many describe as the most user-unfriendly part of the procedure.

The web statement provides a description of the virtual screening procedure (okayed for general coverage in a November 2003 rule-making; see sidebar for current coverage and the virtual colonography technologies cleared by the FDA.).

It then says this procedure is best described as an "intermediate" type of test, since it offers no method of removing dangerous or suspicious polyps, and those with such polyps must be sent on to standard colonoscopy which enables their removal.

The statement cites authorities emphasizing the requirement that any screening procedure should be able to "alter the natural history of disease in a significant proportion of those screened," especially necessary when those being screened are asymptomatic – indicating that without such significant alteration, scanning offers little benefit.

(Along these same lines, a recent research report in The Lancet argued that the use of CT and other scanning modalities does not improve outcomes for patients with low back pain, if there is no indication of "a serious underlying condition.")

CMS launched the analysis of the virtual colonoscopy reimbursement policy last year, including an overview of the available evidence concerning the procedure. It then provided a review of this evidence last November in a meeting of the Medicare Evidence Development & Coverage Advisory Committee (MedCAC).

Among the evidence looked at, CMS cited a study indicating CTC "as sensitive as colonoscopy for large adenomas and colorectal cancer." But that study also found CTC possibly "less sensitive for smaller adenomas."

That study also referred to "[p]otential radiation-related harms, [and that] the effect of extracolonic findings, and the accuracy of test performance of CT colonography in community settings remain uncertain."

Besides its wording undermining the value of CTC specifically, the statement offers a negative critique of CT technology in general.

It notes the increasing promotion of "whole-body CT imaging" for "healthy, asymptomatic individuals." But it says that the FDA has found no evidence that these procedures are significantly effective in detecting diseases or reducing the incidents of "premature death."

It adds: "Any such presumed benefit of whole-body CT screening is currently uncertain, and such benefit may not be great enough to offset the potential harms such screening could cause." The statement goes on to refer to the use of "ionizing radiation" and this has been generally seen as producing downstream cancers, if over-used, especially in children.

Importantly, CMS is seeking public input over 30 days not just on CTC in general but, specifically, on cost-benefit issues. And the statement notes that an expert panel already has issued a conclusion on that issue at the November MEDCAC session.

CMS asked panelists to rate their confidence that virtual colonography "has a similar ratio of cost per Life Years Saved, as compared to optical colonoscopy."

It said that the average numerical vote by the panelists was just 1.55, "midway between 1 for 'no confidence' and 2 for 'little confidence.'"

Finally, the CMS statement reviews a variety of organizational opinions on the technology, all essentially concluding that CTC cannot yet be considered standard of care for colorectal cancer screening.

CMS says that colorectal cancer remains a leading cancer but that there have been recent declines, possibly associated with increased use of screening procedure.

It cited figures that between 2000 and 2005, the percentage of those 50 and older reported an increase in colonoscopies from 20% to 39%, though a decrease in fecal occult blood testing decreasing from 17% to 12%.

Overall, it said that colorectal screening among those 50 and older increased from 27% in 1987 to 50% in 2005.