Monday, January 24, 2005

The demise of whole body scanning

A little while back, I wrote a piece on my experience nearly two years ago dealing with a medical company heavily advertising whole body scanning, screening breast MRI, and heart scans. The company was AmeriScan, and what got me involved was their deceptive claims on radio ads grossly exaggerating the shortcomings of mammography. When I complained, a company flack justified AmeriScan's claims that MRI was far superior to mammography as a screening test for breast cancer by pointing to two small studies that did not even address the claim they were making. Instead of looking at MRI use in the general population for screening, the two carefully selected studies looked at a very small and very specific group, young women with genetic mutations that are known to predispose them to breast cancer. These two studies showed that, in this limited and specific group, MRI was far more effective than mammography in detecting cancers at an early stage. There's a problem, though. Mammography has long been known to be less sensitive in younger women (which is one reason that it is not generally recommended for screening in women under 40, absent some clinical indication for it, such as a lump, nipple discharge, or other abnormality). Also, this population, with BRCA1 and BRCA2 mutations, is at a very high risk for developing cancer at a young age, and it has been known that mammography is not as useful in women with these mutations. They have a much higher incidence of cancer than the usual population undergoing screening mammography. This combination of factors, lots of tumors in patients with dense breasts that make masses and calcium deposits harder to distinguish, made mammography much less effective in this group. Given that MRI seems to be much more sensitive, it is not surprising that MRI would be much more effective in this select group of women.

But that's not how AmeriScan was marketing their breast MRI scan. They were marketing it as a screening tool, and claiming, based on the above studies, that mammography missed 2/3 of breast cancers (it doesn't) and that MRI picked up 100% of cancers (it doesn't). Given my experience with AmeriScan, when I perused the Sunday New York Times and noticed on the front page an article about how scanning companies are now hitting hard financial times, I immediately read it before looking at the rest of the paper:

It began as a sort of medical gold rush, with hundreds of scanning centers, with ceaseless direct-to-consumer advertising, and with thousands of Americans paying out of pocket for the scans, which could cost $1,000 or more.

It ended abruptly with the wholesale shuttering of businesses.

CT Screening International, which scanned 25,000 people at 13 centers across the nation, went out of business. AmeriScan, another national chain, also closed. So, radiologists say, did another company that put scanners in vans and traveled to small towns in the South.

The business's collapse, health care researchers say, holds lessons about the workings of American medicine.It shows the limits of direct-to-consumer advertising and the power of dissuasion by professional societies, which warned against getting one of these scans. The tests, they said, would mostly find innocuous lumps in places like the thyroid or lungs, requiring rounds of additional tests to rule out real problems, and would miss common cancers, like those of the breast.

It also shows the workings of the medical market - when insurers refused to pay, requiring customers to dig into their own pockets for the tests, scanning centers found themselves cutting prices to compete. Within a year, some centers said, prices fell to less than $500 from $1,000 or more.

But what really caught my eye is the following:

The scans were something new in American medicine - not like traditional screening scans, mammograms or colonoscopies, for example, in which patients are overseen by their doctors. People requested these scans on their own. They paid on their own, with no hints that insurers would start picking up the bill. And the reports came to the customers, not their doctors.

Some proponents said the scans would enable people to take their health care into their own hands.

This is exactly the same pitch used by alties when advocating the wider availability of "alternative medicine" treatments or railing against the conventional medical establishment. They often claim that permitting these treatments represents "health freedom" (see also here and here) and that regulating them somehow impinges on that "freedom." After all, who could be against "freedom"? The problem is, "freedom" to choose is meaningless if the patient is not given the information necessary to make a truly informed choice. Alternative medicine practitioners rarely give patients scientific studies that tell how well their therapies truly work, either because such data do not exist or because they do not acknowledge studies that fail to show any efficacy. The same principle, I think, was at work in terms of these body scanners. So what are the potential negative consequences of these scans that patients were not generally made aware of? Well here's one:

Dr. Barnett Kramer, director of the National Institutes of Health's office of disease prevention, said: "For every 100 healthy people who undergo a scan, somewhere between 30 and 80 of them will be told that there is something that needs a workup - and it will turn out to be nothing."

Indeed. Such abnormalities used to be known as "incidentalomas." Incidentalomas are unexpected lesionis discovered on an imaging study done for other reasons. They first became a problem as CT scanning for trauma became more widely available and we discovered that they are much more common than expected. Whole body scanning is, in essence, looking for incidentalomas. If the abnormality is in the breast, perhaps working it up is not that big a deal. Breast biopsies, though not pleasant, are seldom dangerous. However, what if the lesion is in the lung, or a major abdominal organ? There is a risk of life-threatening complications from biopsying such lesions. For example, perforation of the intestines or stomach is an inherent risk in sticking needles into the abdominal cavity to biopsy lesions, resulting in the need for emergency surgery. The risk is relatively small, but it exists nonetheless. If whole body scanning became more prevalent, such complications would become less uncommon. There's another problem. Although the radiation dose of a single CT scan is relatively low, having several of them over several years (which, apparently, firms such as AmeriScan would encourage) does produce a radiation exposure that measurably increases one's risk of various cancers. Finally, one should not underestimate the anxiety patients go through when told they have an abnormality. I see this all the time with women coming in for evaluation of abnormal mammograms, most of whom do not have cancer.

Of course, one could make an argument (and the radiologists selling these scans, like Dr. Craig Bittner, founder of AmeriScan, did) that the risks of additional tests, additional radiation exposures, and the risk of complications from biopsies are outweighed by the benefits of finding tumors early or finding heart disease early. The problem is, with certain narrow exceptions of high risk populations (detecting lung cancers in smokers, for example), there is no evidence that such scans provide a benefit in terms of improved detection and survival. In essence, the incidence of cancers or abnormalities in an asymptomatic or otherwise healthy population is so low that most findings will be false positives. There's a reason insurance companies wouldn't pay for them. Sure, there will be a few cancers found that wouldn't otherwise have been found, which will lead to glowing testimonials (very similar to alternative medicine testimonials) about how scanning "saved" the patient's life. But the vast majority of findings will be either no finding at all or false positives. (Why this is true would make a good topic for a post of its own; I'll add it to the queue of future topics.) Remember, this is screening what is, in essence, an asymptomatic population. It's also screening a population that is well-off enough to afford to pay for these scans, which suggests the screening is being done in a population that is already likely to be healthier and have better access to health care than average.

I won't mourn the passing of these companies. Once again, recall what I said regarding evaluating therapies or diagnostic tests, whether conventional or alternative: The claims of conventional medicine and alternative medicine should be treated the same and that they should be held to the same standard of scientific and clinical evidence. I do not differentiate between the two when considering evidence, nor should you. You should treat the claims of any company that is selling a high-tech test with just as much skepticism as any altie claiming to cure cancer. Look for randomized clinical studies, not testimonials, and try to make sure that the studies cited actually address the claim that the company is making. Just because it's high-tech doesn't mean it's necessarily better.

4 example(s) of insolence returned:


At 1/24/2005 9:49 AM, Blogger Pat in NC said...

The presence of incidentalomas indeed causes anxiety. I had a spiral scan of my chest which diagnosed PE after a weeks history of chest pain, elevated temp. course of antibiotics and ending with coughing up blood. When I got the report (after appropriate treatment for the PE and diagnosis of PTT LA elevation) the radiologist's finding of an incidentaloma of my adrenal caused far more concern on my part than my original problem. I was very relieved when my physician explained the common occurence of these benign incidentalomas.

 

At 1/24/2005 10:00 AM, Blogger Orac said...

This comment has been removed by a blog administrator.

 

At 1/24/2005 10:15 AM, Blogger Orac said...

Actually, now that you mention it, a while back my mom had an incidentaloma. I had to try reassure her that it was nothing to worry about. Because she was my mom, even knowing what I know about these things, I still couldn't help getting a little worried myself. She ended up needing repeat scans to make sure the lesion was not growing.

As a doctor, it's hard to deal with these things as well. Medicolegally, you're screwed if you don't investigate and the patient is one of the few in which the incidentaloma turns out to be cancer.

 

At 1/10/2006 4:06 PM, Anonymous Anonymous said...

the Ameriscan full body MRI was a life saver for me and my mother then someone comes along and takes it away from us. you denied us the right to health care and I hope some day you regret that!

 

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