_{Published on December 21, 2021}

CT colonography (CTC) is an abdominal/pelvic CT exam with the colon insufflated with room air or CO2, following a bowel preparation to optimize visualization of the mucosa. Postprocessed images of the colon include both 2D and 3D images for interpretation with or without a three-dimensional flythrough of a “virtual colonoscopic” view similar to optical colonoscopy. The American College of Radiology (ACR) appropriateness criteria list indications for diagnostic CTC exams in symptomatic patients. Importantly, CTC is also listed by the ACR appropriateness criteria and the United States Preventive Services Task Force (USPSTF) recommendations as an indicated exam for colorectal cancer (CRC) screening in asymptomatic people of an appropriate age. The sensitivity for detection of polyps 6 mm or greater in size and for advanced neoplasia equates to that of the optical colonoscopy (OC), which is the only other available direct visualization test of the entire colon that can lead to prevention of CRC, not just detection. This is an important distinction, as prevention of CRC can be achieved by finding precancerous polyps with the use of direct-visualization tests, enabling subsequent surgical removal. Considering CRC is the second-leading cause of cancer death in the United States, and it is mostly preventable through screening, the importance of prevention with CTC is amplified. Additional CRC screening options include stool-based tests, which have high cancer detection rates, but less sensitivity for detecting precancerous lesions.

Because CTC provides high sensitivity for polyp detection and doesn’t require anesthesia, it is an ideal service for radiology practices. Establishing a CTC service requires a simple, but organized plan that can be easily followed by those involved in the project, as well as understood by those who have financial responsibility. A practical starting point is finding a program champion who can drive three simple phases: visioning, analysis, and implementation.

Visioning Phase

During this aspirational phase, the radiologist champion collaborates with other interested parties to establish a vision, mission, and set of objectives for the endeavor. A clearly stated vision keeps everyone aligned to the goals in establishing a CTC service. For example, “By 2025, we will establish a CT colonography program to screen patients for colorectal cancer, inclusive of follow- up evaluations per recommendations by the USPSTF.” The champion is also responsible for identifying stakeholders, such as hospital administrators, ACO administrators, colleagues from within the practice and from external referring services, and, importantly, patients who value such an initiative.

Analytical Phase

During the analytical phase, the radiologist or project champion decides whether the project can or should be proceed. The project champion might consider conducting a “SWOT” analysis to determine current strengths and weaknesses, as well as potential opportunities and threats:

Strengths

• New multislice CT scanner
• CT scanner underutilized
• OC appointments backlogged
• Gastrointestinal (GI) service supports CTC initiative

Weaknesses

• One radiologist trained in CTC
• Insufflation device needed
• CT technologists untrained

Opportunities

• CTC technologists’ career advancement
• Federal incentive programs for hospitals include increased colon cancer screening
• Understaffed GI service
• Low CRC screening compliance

Threats

• Hospital aggressively recruiting new GI physicians
• Family practice MD training to perform OC
• Stool-based tests to resolve backlog, though less accurate for detecting precursor polyps

Another consideration is an assessment of the market using “Porter’s Five Forces”—a method for analysis taking into consideration the competition (other radiology practices, or medical specialties); suppliers of colon evaluation (gastroenterologists and colorectal surgeons); service purchasers (patients and insurance companies); and threats of substitutes (stool-based tests, fecal immunochemical tests, and blood tests). For example, “Are screening and diagnostic CTC already offered by gastroenterology or colorectal surgeons in the health system or nearby?” Asking such questions will drive an analysis of whether a successful CTC service can be achieved in the face of competition or whether it cannot be achieved due to market saturation or other forces. Moreover, can the CTC service synergize with current programs, resulting in an ideal collegial opportunity, with more specific direction of high-yield colonoscopies and improved resource allocation?

An added benefit to performing such an evaluation is the production of a financial analysis, which may guide stakeholders, such as hospital administrators or practice partners, in decision making. Such an analysis can be a simple income statement weighing the projected revenues, compared to the expenses. A financial analysis also shows downstream revenues to the affiliated hospital (e.g., increased early-stage as opposed to late-stage CRC surgeries, which may be a benefit to academic and private health systems and, ultimately, the patients).

“Heavy Lifting” Phase

Once the project has been approved by the various stakeholders, it is time to act. The first step is to identify gaps between the current and future states. Common tools include developing a timeline for implementation, creating a checklist, and determining milestones that need to be achieved to stay on target:

• 8 Months Out—Establish training plan for radiologists and CT technologists
• 7 Months Out—Purchase all equipment (insufflator device, rectal catheter, oral tagging solution)
• 6 Months Out—Create digital and paper patient instructions
• 5 Months Out—Create order sets in hospital EMR and version to send providers outside system
• 4 Months Out—Set scheduling rules
• 3 Months Out—Draft memo on “Go Live” date for marketing
• 2 Months Out—Complete training for radiologists and technologists
• 1 Month Out—Test “Go Live” with three pilot patients
• “Go Live”—First day of program launch

For many practices, defining the current state will be straightforward (i.e., where no CTC program exists, begin with whatever CT services are offered). It is also possible that the practice has no other competing or complimentary services that have surfaced during the analysis phase. The next step is to determine how a future state will look based on that vision. Finally, set up benchmarks that must be met within the desired time frame. This can be done using a Gantt chart or a simple timeline. Start by creating a task list:

• Inventory equipment
  • Identify location(s) and CT machine(s) that will be used for performance of procedure
  • Purchase CO2 insufflator and CO2 tank supply
• Establish imaging protocol
• Create bowel preparation protocol with patient instructions
• Obtain needed supplies, such as tagging solution and balloon-tip rectal catheter
• Perform information technology- and billing-related tasks, such as creating order form or electronic orderable, setting fees, and building dictation template
• Hire and train patient navigator
• Draft standard patient letters (normal, follow-up required, referral to specialist)
• Create scheduling template
• Train radiologists

Once these tasks and milestones are complete, a CTC service can begin, thus providing an excellent opportunity for patients to avoid a potentially preventable cancer through successful screening. The system will also be effective for necessary added value diagnostic CTC exams, benefiting patients who are unable to undergo OC for assessment.

The Next-Level Goal

Once a successful CTC service has been established, a next-level goal is to launch a multidisciplinary program in collaboration with gastroenterologists, surgeons, and oncologists to provide options for screening candidates and to provide swift follow-up action for abnormal findings. Prior to 2021, the age of recommended initial screening for those at average risk was 50. Approximately one-third of eligible screening candidates remained unscreened, and yet, there were access resource constraints. Now that the age for initial screening has been lowered to 45, access challenges to screening tests have continued to increase. The use of CTC as part of a multidisciplinary program, with options made readily available to screening candidates at first contact, may be more successful in reaching those who otherwise remain continually unscreened. As experts commonly say, “the best test is the one the candidate will do.”

Establishing a CTC service is not an insurmountable task, but one that can be more easily implemented with detailed organization, as is common to most initiatives in radiology involving cross-sectional imaging. This article is meant to provide one guiding template to establishing a CTC service, with room for variation as needed by the project champion. Establishing a CTC service is an excellent opportunity for radiologists to provide and demonstrate added value to a partner hospital or health system in today’s health care market, which is changing into a “fee for performance” model focused on quality outcomes. Metrics, such as the percentage of a population managed within a given health system that has undergone CRC screening, are valuable to hospitals competing for federal incentives (e.g., Health Care Effectiveness Data and Information Set metrics for CRC screening). Therefore, CTC programs are valuable to radiology practices in demonstrating added value to such institutions. The ability to provide a CTC service can serve as a unique bargaining chip for private radiology practices vying for new contracts, or for academic radiology practices in need of quality contributions meaningful to population health. Moreover, establishing a CTC service can provide a more convenient option for patients in need of CRC screening, which can result in fewer deaths from CRC.

CTC and COVID-19

A discussion of establishing a CTC service would be incomplete without discussing that service in the setting of the coronavirus disease (COVID-19) pandemic. The benefits of a CTC service in that context are multifold. CTC can be performed with less use of PPE, which may be in sparse supply; the risk of exposure for the radiologist and technologist are lower, compared to an anesthesiologist and colonoscopist in a positive pressure room; fewer health care workers are exposed per screening candidate, and those health care workers can remain socially distanced from respiratory exposure throughout the procedure. CRC screening should be considered a necessary ongoing service during the pandemic, given the high likelihood of increased cancer mortalities, if screening is not ongoing.