CT colonography’s proven clinical worth now invites reimbursement

What radiologists gleefully celebrated almost a year ago has been officially validated for the entire medical community by The New England Journal of Medicine: CT colonography is an accurate alternative to colonoscopy to detect suspicious polyps and is primed for colorectal cancer screening. Virtual colonoscopy proponents say CTC is also ready for reimbursement.

The American College of Radiology Imaging Network's National CT Colonography Trial (ACRIN 6664) was the largest multicenter prospective study comparing CT colonography with the gold standard colonoscopy. Principal investigator Dr. C. Daniel Johnson and colleagues at 15 institutions nationwide enrolled 2600 asymptomatic subjects aged 50 or older.

Based on complete data from 2531 participants, the investigators concluded that CT colonography could detect polyps 1 cm or larger in nine out of 10 patients. Results matched those obtained with colonoscopy for intermediate to large-sized adenomas.

Johnson released preliminary results last September at the 2007 ACRIN fall meeting and then submitted the data to review for publication. The final results have validated all previous studies on CTC's role in colorectal cancer screening, according to researchers. The findings appeared in the Sept. 18 issue of the NEJM.

"CT colonography could be adopted into the mainstream of clinical practice as a primary option for colorectal cancer screening," said Johnson, a radiologist at the Mayo Clinic in Scottsdale, AZ. "We hope that this additional, less invasive option for cancer screening will lead more people to get screened and will ultimately result in fewer deaths from colorectal cancer."

The publication of ACRIN 6664 means the end of an arduous, sometimes frustrating process toward validation of CTC as a reliable clinical tool, said Dr. Perry J. Pickhardt, an associate professor of radiology at the University of Wisconsin Medical School in Madison.

"This confirms what we showed dating back to 2003 in our original NEJM study. The next logical step is widespread reimbursement and actual implementation," Pickhardt told Diagnostic Imaging.

Publication of the ACRIN 6664 completes the puzzle needed to prove that CTC, when used appropriately, is better, faster, safer, and cheaper than colonoscopy, according to Pickhardt. With nothing left to prove, the scene is ripe for Medicare and all other major national payers to get ready to reimburse physicians for the procedure.

"It may happen sooner than people think," he said.

The Centers for Medicare and Medicaid Services is expected to issue a proposed decision memo on CTC screening coverage Nov. 11, 2008. A final decision analysis for national coverage should be published by Feb. 17, 2009.

Recently published studies suggest the current installed capacity of CT scanners could handle colorectal cancer screening. The only question remaining is whether there are enough interested and qualified radiologists to cover demand for the exam, according to Pickhardt.

"That would be the big issue," he said.

For more information from the Diagnostic Imaging archives:

Available scanners tackle future CTC screening demand

Radiology societies seek Medicare coverage for CT colonography

CMS commences national coverage analysis for CT colonography

CT colonography CAD trial could quicken regulatory approval