CT Colonography in the News

You have probably read about the CT Colonography study highlighted in this week’s New England Journal of Medicine and asked:

1)Is this the study conducted by the American College of Radiology Imaging Network?

2) What is the difference between the study published in NEJM this week and the ACRIN study?

3) Why has the ACR not released further details or made an official statement?

The answers are:

1) The NEJM study is not the ACRIN trial. The study published in NEJM is a large single site trial whose principal investigator is ACR member, David H. Kim, M.D., of the University of Wisconsin. 

2) The ACRIN trial is a large, multicenter trial. ACR member, C. Daniel Johnson of the Mayo Clinic, Scottsdale, Arizona is the principal investigator. He presented the results of the trial at the ACRIN meeting last week.

3) Because it has not been published yet, neither the ACR nor ACRIN can make further details available, in accordance with the publication guidelines of the major scientific journals. The ACRIN trial is expected to be published in the coming months, at which time the College will use every available avenue to give members the latest on this important trial and continues to educate government and private payers as to the benefits and limitations of CTC.

In the meantime, I want to know your take on CT colonography. If studies continue to show the viability of the exam as a screening tool, do you think that you or your colleagues will seek out training in the technique? How do you see the performance of CTC fitting into your practice?

Let’s Talk!

Harvey L. Neiman M.D. FACR
Executive Director
American College of Radiology

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Comments

[Mickey Guiberteau, MD]

With the encouraging results of the ACRIN CT Colonography Trial and the NEJM-published Wisconsin study demonstrating similar sensitivity and specificity between optical and virtual colon screening techniques and an absence of notable complications with CT, use of the latter technique is poised to assume a mainstream role in screening for colon cancer.

This is indeed an opportunity for my own group to provide the service in our practice. However, it will also undoubtedly provide challenges to our efforts from those physicians who see this as a looming threat to a very important and lucrative part of their gastroenterological practices.

This will inevitably intensify as reimbursement expands. ACR should be commended for its CT colonography education initiatives at the new ACR Education Center. We will certainly take advantage of this opportunity, as we view the present circumstance as a chance to obtain the necessary expertise and experience to establish a foothold in providing the service.

However, like other practices, ours has been at this juncture before with other technological innovations. We have successfully maintained our leading role in some, but have virtually lost our dominance in others. While all such situational outcomes depend heavily on local relationships and politics, our radiologists will look to the ACR to provide continued assistance in asserting our competitive edge in CT colonography and to persist in efforts to further contain the anti-competitive practices in medicine which often trump the efforts of quality and competence in the services we offer.

Mickey Guiberteau, MD

Greater Houston Radiology Associates

[Mark E. Klein, MD]

I note there have been few comments so far on Virtual Colonoscopy (VC). I hope this is not indicative of the level of interest in this procedure.

VC offers the opportunity to dramatically alter the incidence of colon cancer. The vast majority of colon cancers can be prevented by timely removal of advanced adenomas, the target lesion of colon screening.

VC is an excellent technique for safely and accurately identifying these lesions, and offers real hope in decreasing the morbidity and mortality from colorectal cancer.

Many screening candidates have avoided optical colonoscopy due to the invasive nature of the procedure, the not insignificant risks, and the need for sedation and loss of a day's work, and will accept VC as an alternative.

Since over 50 million Americans require colon cancer screening, VC represents a huge opportunity for radiologists to impact the disease and to broaden their practices. In my opinion, we need not concern ourselves with turf battles.

If we commit to performing VC studies with optimum technique there will be no shortage of patients in the coming years. The single potential greatest obstacle to the success of VC would be the failure of our specialty to embrace this technique and to perform it at a high level.

Mark E. Klein, MD

[Steve Meshkov MD]

What is the current status of reimbursement for CT colonography?

Steve Meshkov MD

[William A. Ladd, M.D.]

I have long been fascinated with the attention given to CT colonography. I can't figure out why, since the patient still needs to go through a bowel prep, and still gets his or her colon uncomfortably inflated like a balloon. Then, if anything is found, a fiberoptic colonoscopy is necessary for biopsy or polypectomy.

A friend of mine had both CT colonography and fiberoptic colonoscopy peformed as part of a study years ago. He said he would always have the colonoscopy from then on. I believe the reason was just that he was given a benzodiazepine for the colonoscopy but not for the CT colonography. But then that's the point: For some reason, people assume that patient discomfort and inconvenience is so much less with CT colonograpy. Wrong. My personal choice (I'm soon to turn 55) is fiberoptic colonoscopy, the same choice as every radiologist I know personally.

I think CT colonography has an element of "The Emperor's New Clothes" to it.

William A. Ladd, M.D.

[Harvey L. Neiman M.D.]

Currently Medicare pays for diagnostic CT Colonography in 48 of the 50 states in the U.S. as well as in Puerto Rico, U.S. Virgin Islands, and the District of Columbia for those instances where patients have undergone a failed colonoscopy.

Some states have additional coverage for certain medical conditions, such as a patient’s inability to tolerate a colonoscopy. A majority of the private payers are also paying for diagnostic CT colonoscopy.

Only one private payer has agreed to pay for CTC as a screening study. Otherwise, the Medicare carriers do not have the authority to pay for CTC as a screening study unless they are told by national Medicare that it is a covered service.

The ACR will continue to work with the Centers for Medicare and Medicaid Services (CMS) and Capitol Hill to gain coverage for screening for colorectal cancer using CTC.

The recent University of Wisconsin trial and the upcoming ACRIN National CT Colonography Trial will, no doubt, help in the effort to bring about sensible reimbursement for this exam.

Harvey L. Neiman, M.D.
Executive Director
American College of Radiology

[Philip Grimm MD]

I am just getting into the Colonography area, and am not yet doing any, but I have been involved with on site demonstrations of the work stations from all of the major venders, specifically for colonography.

Some very Brief background: I refer you to some of my frequent-beligerant/annoying/?? blog postings on other issues: I left my prime time group and am now working for a local VA domicillary. This VA cannot get our local gastroenterologists to do their colonoscopy's, and they want an alternative.

Further background: I've had 3 colonscopy's and the event has changed, the new meds leave no hangover and you could go back to work immediately, or at least function for the rest of the day-and it's fast. So we are competing with a mature product.

The gastroenterologists are joking that it only takes them 2-5 minutes to do one exam! Now, granted that it was taking them 20-40 minutes to do a single exam 10 years ago. But we can't do that. That also raises the question: what are they missing if they are being that casual about their procedure?

Now, in looking at all the workstation approaches to this problem, it seems so artificial and obviously dependent upon display algorithms that it crosses my line of comfort. The built in one dimensional depth cues and the color-coding is obviously fake. But the attempt to reproduce the live colonoscopy effect is very convincing. I'm not sure that I like the filleted display...

It is easier to tell feces from polyps than I thought it would be, but I don't know enough about polyps to know sessile from pedunculated... It's also my impression that huge cancers can be ignored more easily than small polyps..

I find myself looking more at the regular axial CT image pertaining to the area in question, once I think I have found a polyp, and the advantage to that is that I think you can estimate degree or level of invasiveness.

The images are also very pretty, and they sure are different than that which we have been looking at for so long.

I don't think this is ready for the "real world" --if you could call private practice a real world--but I do think I can use this and actually help some of these old veterans who otherwise wouldn't get their colon's examined.

It's a lot of radiation too--prone and supine acquisition. Also, it seems to be as tech dependent as ultrasound.

And I think there will be "blind spots" around the ileal-cecal valve and around the balloon catheter... Sharp curves make me nervous too...

But I do think it will work, and I bet I can convert the twenty or so internists who share my new practice. They are skeptical and they do not want to be "experimenting" on their patients, so it may be a harder 'sell' to the referring physicians than you may think.

[Alfonso Gay, Jr., M.D.]

The technology behind CT colonography is certainly impressive, however, I sense there is a lack of interest amongst radiologists for several reasons. Despite the impressive results recently announced prior studies have discussed the length of time involved in proper interpretation. If you can perform a Ba enema faster this may result in a lack of interest.

As with CTA you are responsible for all the images not just the computer generated 3D images etc. With current multislice scanners we're talking about several hundred images. How much will we be paid for our efforts? Is it more than a standard CT abd/pelv?

The imaging workstations required are expensive. What kind of volumes can we anticipate in light of the fact that the technology is being denounced by the governing body for gastroenterologists?

Alfonso Gay, Jr., M.D.

[Shailendra Chopra, MD, MRCP, FRCR]

I started doing CT colonography in my practice almost two years ago and have so far limited it to patients who had incomplete conventional colonoscopy. I have been doing about two cases a week. We work in these patients directly form our endoscopy suite. This is what my take is on this topic.

1. For at least some time, conventional colonoscopy will be the method of choice for looking at the colon for the purpose of cancer screening. As radiologists we should be ready to acknowledge that openly.

2. However, the penetration of conventional colonoscopy in the population at risk is incomplete (pun intended!). Despite all attempts at health education there is and will be, in the foreseeable future, a significant number of people who are resistant to undergoing conventional colonoscopy for unfounded reasons of their own. A lot of them will accept CT colonography because it appears less invasive. These same people will be much more ready to have a conventional colonoscopy once the CT colonography is abnormal. So, really it is a good situation for all. Radiologists create new business, gastroenterologists get more business as a byproduct and, MOST importantly a greater proportion of population gets screened for colon cancer.

3. Until prepless CT colonography becomes a workable reality, colon prep is going to be the most difficult part of the exam. Therefore setting up a screening CT colonography service will require working closely with the endoscopy service so that all patients with positive CT exams can have conventional colonoscopy the same day.

4. The time taken to interpret this exam is of importance. When it comes of age, the virtual dissection software will be of much more use than the fly through techniques because you can read it like a strip of EKG.

5. Radiation dose is a concern but majority of these patients will be in their 50’s or above and remember MR colonography is already closer than the horizon.

The days of screening CT colonography are not far. The technology, experience, reimbursement are all almost there. I predict having to buy CT scanners dedicated only to this procedure, once these things come together.