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Shared Prevention

Collective colon cancer screening data is at radiologists’ fingertips.
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I think the medical community is pretty convinced that CTC is the right thing to do. Insurance makes things more complicated.

June 01, 2021

“As an abdominal radiologist, it is not uncommon to see patients who have never been screened present with abdominal pain from an obstructing colon tumor — and disease that has already spread,” says Courtney C. Moreno, MD, chair of the ACR’s CT Colonography (CTC) Registry Committee, associate professor in radiology and imaging sciences at Emory University, and a member of the ACR Colon Cancer Committee. “It’s so sad to me that people are still dying of colon cancer when it is preventable or treatable with early detection.”

For more than a decade, the ACR’s CTC Registry has provided evidence-based health outcomes and data for decision-making — allowing facilities to compare their results regionally and nationally (learn more at Process measures include rate of adequacy of diagnostic CTC examination and rate of adequacy of screening CTC examination. Outcome measures include rate of colonic perforation, true positive rate, and extracolonic findings. Data collected in the CTC Registry evaluate colonography as an alternative to colonoscopy. Participating facilities and physicians can review reports based on aggregated data to facilitate patient safety and boost quality improvement efforts.

The Bulletin recently talked with Moreno about the importance of colon screening and the CTC Registry — an invaluable tool connecting radiologists who want to gain insight about CTC exam performance at their institution and demonstrate improved patient outcomes.

Why is staying current on colon health so important?

Colorectal cancer is the second leading cause of cancer death in the U.S.1 So much of what we do in radiology in the cancer space is seeing people who have already been diagnosed — to determine if their cancer is getting better or worse. CTC is really a way to diagnose precancerous polyps that can be removed — preventing cancer. There are a lot of different options out there — from CTC to screening optical colonoscopy to stool-based tests. The American Cancer Society says the best test is the one that patients are willing to undergo. Even with all of the tests that are available, the estimated percentage of the American population who say they are up-to-date with colorectal cancer screening is only around 68%.2 And that number may be artificially high because the data comes from phone interviews by the CDC — relying on self-reported data about tests done as long as a decade ago.

Which colon screening exam would you recommend?

CTC. But I would not discourage anyone from getting any of these colon screening tests. The stool-based tests are potentially easier for patients to undergo because with some of the tests you produce the sample in the privacy of your own home and mail it off for testing. A limitation of stool-based tests, however, is that their ability to detect polyps and advanced neoplasia is lower than the structural examinations of the colon — which include optical colonoscopy and CTC. There can also be some false positives with the stool-based tests, so patients end up getting a colonoscopy or CTC anyway.

Are there other advantages to CTC?

From a patient- and family-centered care perspective, CTC is much safer than optical colonoscopy. With the floppy catheters we are using now, there is essentially no risk of perforation. You can also get a CTC without sedation, while optical colonoscopy requires sedation. That means that to undergo optical colonoscopy you need to recruit a friend or family member to accompany you or drive you home because of the sedation involved. We know that one reason for low screening rates is the challenge of taking time off of work and finding someone else (who may also be of working age) to go with you. People may have childcare responsibilities or take care of older family members. Whatever the case, it is tough for them to devote a day or two to the test — prepping the day before and then recovering from sedation the day of the exam. With a CTC, you can work the day before the exam, start the prep the night before, have your CTC done in the morning, and go back to work the same day.

Why should ACR members participate in the CTC Registry?

Participating radiologists and sites can use the CTC Registry as a way to compare their facility’s performance to other registry participants. That means they submit data and receive regular reports on things like radiation dose, the number of exams that were of acceptable image quality, the true positive rate, the number of exams that found a polyp a centimeter or larger in size — among other findings that have been entered into the registry for others to learn from. Participants get reports in graph form, allowing you to keep tabs on how you are doing compared to other places. It really helps us as a field to learn from each other and to collect data to help us advance the practice of CTC.

Even with all of the tests that are available, the estimated percentage of the American population who say they are up-to-date with colorectal cancer screening is only around 68%.

How do you submit data if you want to participate in the CTC Registry?

There are two main ways to submit data. If a practice prefers, it can submit information about individual exams using a web form. A low- or medium-volume practice may prefer to do it that way — submitting data as they go for each CTC exam. Practices can also submit the data in a batch through a spreadsheet. The ACR provides participating sites with a spreadsheet to fill in and upload to the registry. Practices generally identify someone like a CT technologist, a nurse practitioner, or an administrative employee to submit data to the registry. The ACR has put together a start-up guide at to walk people through the process of enrolling in and submitting data to the CTC Registry.

Are cost and coverage of screening issues for patients? Is this a discussion that radiologists should have?

I think the medical community is pretty convinced that CTC is the right thing to do. Insurance makes things more complicated. There is a commercial insurance mandate as part of the Affordable Care Act (ACA) of 2010 for any screening test graded as an A or B by the U.S. Preventive Services Task Force (USPSTF). Commercial insurance coverage of screening CTC is therefore mandated by the ACA based on its A grade from the USPSTF. A small caveat to that is that about 12% of commercial insurance plans (those in existence before Sept. 23, 2010, and not substantially altered since 2010) are grandfathered in and therefore not required to cover the screening exams mandated by the ACA, although many of these grandfathered plans have also decided to cover USPSTF-recommended screening exams including CTC. While the commercial insurance market mandate is part of the ACA, Medicare does not cover screening CTC.3 Medicare non-coverage is something we see as an issue. We have to tell those older patients that they will potentially have to pay out of pocket for CTC. Because of that out of pocket cost, some Medicare patients are unable to undergo CTC because they cannot afford it. Using CTC Registry data, we found that the lack of Medicare coverage of screening CTC disproportionately impacts CTC utilization by minority patients as compared to White patients.

What are some things members might not know about participating in the CTC Registry?

Participation in the registry allows you to get credit for the ABR’s Maintenance of Certification Part IV requirements. Members should also know that if their practice already participates in the ACR’s Dose Index Registry or the General Radiology Improvement Database — participating in the CTC Registry is free. That is a big selling point. Even if they don’t participate in those registries, CTC participation is relatively inexpensive. The cost is on a sliding scale based on the number of participating locations and radiologists. It starts at $500 for up to five sites and five radiologists. In terms of medical pricing, that is pretty cheap. Another big selling point is that registry data can be used for research that provides insight into nationwide practice patterns. For example, the CTC Registry team used registry data for the project looking at the impact of Medicare non-coverage on CTC utilization.3 Currently, with more than 17,000 CTC exams in the registry, there is a lot of information about how different practices are performing CTC. The NRDR Data Access and Publications Policy (available at describes the process for requesting support to work with an ACR data analyst to carry out a research project.