The cost advantage of CT colonography (CTC) over colonoscopy in Medicare patients varies widely under a number of clinical scenarios, but a new analysis has found that the savings are there in every one of them—and may range as high as 58 percent.

At the same time, in a base scenario assuming a colonoscopy follow-up rate of 12.9 percent, the average cost savings of CTC over colonoscopy was an impressive 29 percent per Medicare enrollee.

Bruce Pyenson, principal actuary at Milliman, and colleagues there, along with Perry J. Pickhardt, MD, of the University of Wisconsin, arrived at their numbers after examining Medicare claims data, fee schedules and related data sources.

They report their findings in Abdominal Imaging.

The team identified 127,175 Medicare colonoscopies performed in 2013 and classified 56,578 (44 percent) as screening for purposes of calculating average costs.

Using trends estimated by comparing 2013 and 2015 Medicare fees, they estimated 2015 average Medicare colonoscopy screening costs of $1,035.

By contrast, they found, Medicare’s 2015 national fee schedule for diagnostic CTC without IV contrast is $243.

They assumed that total 2015 cost for a screening CTC is the cost of the diagnostic CTC plus the pre-procedure laxative and, for the patients with follow-up colonoscopy, the cost of colonoscopy with biopsy.

Pyenson et al. further documented the significant expense of deep sedation in colonoscopy, which often requires the presence of an anesthesiology professional and costs Medicare an average of $154 per use.

Meanwhile, expensive complications such as those brought on by bowel perforations are not a risk in CTC.

In their discussion, the authors note their study’s consistency with prior studies establishing the cost-effectiveness of CTC screening, especially compared with no screening, as well as the equivalence of clinical efficacy for colorectal evaluation between CTC and colonoscopy.

“When typical non-Medicare charges and extra-colonic findings (e.g., abdominal aortic aneurysms) are considered,” they add, “the cost-effectiveness of CTC increases further” relative to colonoscopy.

In a press release promoting the study, Patrick Hope, JD, executive director of the Medical Imaging & Technology Alliance (MITA) trade group, stresses that the Milliman study confirms that CT colonography meets the “triple aim” that Medicare policies strive to achieve.

“[I]t improves the patient experience as no anesthesia is required, allowing for immediate resumption of daily activities; as an effective screening tool for colon cancer, it improves population health; and it reduces the cost per capita of health care,” Hope says.

“We hope this data will encourage the Centers for Medicare & Medicaid Services to cover this service as it will grant more American seniors access to a cost-effective tool to detect colon cancer early, when it is more treatable.”