Drumbeats & deaf ears

The review “The Time Has Arrived for National Reimbursement of Screening CT Colonography,” published in the July issue of American Journal of Roentgenology sounds like an all-too-familiar story. Will the latest evidence persuade the powers that be to push forward with coverage of a vital screening exam? Or will we remain in limbo?

In the review, Judy Yee, MD, department of radiology and biomedical imaging at San Francisco VA Medical Center, and colleagues meticulously detailed counterpoints that address the primary concerns of the U.S. Preventive Services Task Force in its 2008 review of CT colonography.

The “I,” for insufficient evidence rating, should be reversed as evidence has answered the task force’s questions about radiation dose, extracolonic findings and generalizability to senior citizens, Yee and colleagues argued.

A recent public service announcement took a different approach. Targeted to individuals ages 50 years and older, the message was simple: the most effective colorectal cancer screening test is the one patients undergo. This may be the right message.

That’s because colorectal cancer is highly treatable when detected early. Yet more than one-third of Americans diagnosed with the disease die every year, and late detection plays a large role. The “ick” factor of colorectal cancer screening is off the charts, whether a patient undergoes virtual or conventional colonoscopy.

There are other barriers to dissemination of CT colonography. Some members of the gastroenterology community point out that detected polyps can be removed during a conventional exam. Sort of a two-for-one procedure. Thus, CT colonography patients with suspicious polyps require a second procedure.

A related issue is indeterminate polyps. After reviewing the literature, Yee et al estimated the prevalence of extracolonic (indeterminate or potentially clinically significant findings) in the 10 percent range.

Volumetric assessment via CT colonography may provide a solution for the problematic middle group of polyps in the 6-9 mm range, reported Perry J. Pickhardt, MD, from the University of Wisconsin School of Medicine and Public Health, in Madison, in a study published July 1 in The Lancet.

The study demonstrated the strong link between volumetric growth and clinical relevance. “Volumetric growth of colorectal polyps seems to be a powerful biomarker, which can concentrate the lesions of clinical significance, potentially leaving behind most important lesions.”

Pickhardt and colleagues hinted at another key aspect of the debate: Colorectal screening need not be characterized as an either-or/radiology vs. gastroenterology algorithm. Management of small polyps represents an uncertain space, “for which treatment decisions are contentious [and] could have an enormous effect on colorectal cancer screening, irrespective of modality.”

The CT colonography program at University of Wisconsin is a rare success story, partially because the radiology and gastroenterology departments work together.

Many of the stakeholders in the colorectal cancer screening process—patients, payers, policymakers and physicians—have turned a deaf ear to these pervasive challenges. Meanwhile, Yee, Pickhardt and others have taken leadership roles.

The rest of us can follow the drumbeat of leaders or remain mired in the status quo. How will your practice proceed? Please let us know.

Lisa Fratt, editor