Radiological screening studies look at large asymptomatic populations and are not covered by Medicare or by private insurance carriers, with one big exception-mammography. And until the market forces that propelled screening mammograms into law come into play, these tests will be largely available only to the subjects of scientific studies or to those who can pay for them out of pocket. Thus, they remain largely controversial.

The most popular procedures not covered by Medicare are screening for heart disease and lung cancer, and full-body screening. All three are done with CT and involve ionizing radiation doses greater than that of routine chest radiography, so safety is an issue. Screening for coronary artery disease looks for calcium deposits, the significance of which is itself controversial. Lung cancer screening often finds nodules that are not malignant, but can scare patients and usually mean costly follow-up studies.

Full-body CT is in a controversy class all its own. Screening clinics are springing up across the United States in upscale malls, next to expensive department stores. The mostly self-referred clientele is paying up to $1,200 out of pocket and sometimes finding not only suspicious lesions, but often nonthreatening cancers.

Private insurance carriers generally follow Medicare in deciding whether to reimburse for screening studies. And Medicare never pays for self-referred examinations. According to Heather J. Ohrt, MD, a radiologist and ethicist at the Iowa City Veterans Administration Medical Center, the federal government will not pay for scans unless the patient is referred by a physician.

While some physicians believe full-body CT finds too many things that are not clinically significant, the tests have their adherents and certainly their testimonials.

No shortage of Testimonials

After a $795 full-body scan at the Virtual Physical clinic in Baltimore, the facility last month received this letter:

To Whom It May Concern:

I thank you for saving my husband’s life. He had the Virtual Physical on April 6th. Listed below are the findings:

Throat-large mass at the base of the tongue

Chest-spiculated lesion on lung

Heart-blockage in three arteries

Abdomen-aortic aneurysm (5.3 cm)

I would like to point out that Ed had a physical last March and none of the above was discovered. In six weeks he will have his final surgery and, because of the early findings, he will be fine.

So again, we thank you for saving his life.

Ed and Fran

The ostensible purpose of screening tests is to save lives and to save money. If cancer can be detected earlier, the likelihood of curing it is much greater. If cancer can be nipped in the bud, costly chemotherapy, radiation therapy, and the myriad of other tests and treatments used to prolong life can be avoided.

The Virtual Physical clinic started offering full-body scans last March. Spokesman Jon Hyman says it quickly became evident that there was a lot to be found with this screening.

“We’ve kept a clear database on the results of the scans and we are doing follow-ups on them,” Hyman reports. “We found significantly more pathology than we thought we would. We’ve already received a lot of comment from both patients and physicians on the efficacy of the Virtual Physical and what it’s doing in terms of saving patients’ lives.”

Finding more pathology may itself be a problem. For example, some radiologists like Leonard Berlin, MD-director of radiology at Rush North Shore Medical Center, Chicago, and the North Shore MRI/CT Centre, a joint venture of the medical center and North Shore Radiological Services-say that many people have asymptomatic kidney tumors that will never become harmful.

“There are data [showing] that a lot of small renal cell cancers, if left alone, will never kill a person,” Berlin says. “So now you’re really getting into the gray area. You find a little renal cell cancer and what difference does it make? We don’t know.”

Consumers Union looks on full-body CT with a jaundiced eye as well. Marvin M. Lipman, MD, is a clinical professor emeritus at New York Medical College, Valhalla, NY, and chief medical advisor to Consumers Union. He also writes regularly for Consumer Reports on Health.

“Number one, the cost is prohibitive,” Lipman says. “Number two, the likelihood of the CT scan coming out entirely normal is pretty low. There are many abnormalities, mostly insignificant. However, you don’t know if something is insignificant unless you repeatedly scan it. With the hemangiomas of the liver, renal cysts, and many other things you can find in total-body CT scanning, the problem is repeated CT scans. Most of the radiologists I’ve spoken to wouldn’t be satisfied with less than 2 years’ stability at 4-month intervals.”

Lipman points out that the patient does not know a mass is benign for many months. “It not only is a psychological impact of tremendous proportions, but it results in a lot of unnecessary radiation and sometimes invasive procedures that are totally unnecessary.”

The Dose Issue

Radiation dose is getting a harder look currently. Although low-dose lung CT is just that-lower radiation dose than a diagnostic lung scan-a full-body scan exposes the patient to much more radiation. According to Walter Huda, PhD, a physicist who specializes in radiation dosimetry at Upstate Medical University in Syracuse, NY, a whole-body CT scan could give the patient a radiation dose 200 times that of conventional two-view chest radiography.

“There is only one radiation dose unit that attempts to measure the patient risk for the four [screening] examination types,” Huda says. “This is the effective dose, measured in mrem.”

Huda says that taking a two-view chest radiograph will give the patient an effective dose of about 5 mrem, a two-view screening mammogram results in an effective dose of about 20 mrem, a low-dose screening CT about 50 mrem, and a conventional diagnostic lung CT about 500 mrem. For a whole-body scan, he says, the effective dose will be about 1 rem (1,000 mrem).

“The nominal risk coefficient that is used is about 0.05% per rem (ie, if you get a dose of 1 rem, five in 10,000 exposed individuals may be expected to die of a radiation-induced cancer),” Huda says, “that is, if you believe that current radiation risk estimates can be extrapolated down to doses as low as 1 rem.”

The American College of Radiology (ACR) ethics committee will take up screening studies at its annual meeting this September, while the Radiological Society of North America (RSNA) ethics committee plans to look at the issue at its November meeting.

?Berlin is in the interesting position of being on the ethics committees of both the ACR and the RSNA. The North Shore MRI/CT Centre, where he is radiology director, was one of the first to market lung cancer screening in the mid 1980s, when physician advertising was just becoming accepted.

Berlin’s clinic advertised on local radio at first, but now relies on word-of-mouth referrals from physicians and patients. North Shore charges $325 for a CT of the lungs.

“My attitude is to soft-pedal it, but make the public aware of it,” Berlin notes. “If Mr. Jones is a smoker and high risk, who am I to say no?” Berlin asks. “But to say it is going to be helpful to him may be premature.”

Much of the controversy has centered on the advertising and publicity that have been generated by the radiologists who provide screening to patients, either physician- or self-referred. Harvey Eisenberg, MD, is a Newport Beach, Calif, radiologist who introduced the nation to whole-body CT on? Oprah Winfrey’s TV show. Although he did not return phone calls seeking comment for this report, Eisenberg has been quoted as saying he and his shopping mall clinic have scanned more than 15,000 patients, and “There is not a single human being that I’ve examined that I haven’t found some evolving pathology.”1

A Community Divided

If you subscribe to the what-you-don’t-know-won’t-hurt-you philosophy, this is unnerving news. But this is one of the reasons full-body scanning has not been endorsed by the medical establishment. In a policy statement last November, the ACR discouraged these screening tests.

“The ACR, at this time, does not believe there is sufficient evidence to justify recommending total body CT screening for patients with no symptoms or a family history suggesting disease,” the statement said. “To date, there is no evidence that total body CT screening is cost-effective or is effective in prolonging life. In addition, the ACR is concerned that this procedure will lead to the discovery of numerous findings that will not ultimately affect patients’ health, but will result in increased patient anxiety, unnecessary follow-up examinations and treatments, and wasted expense.”2

Jerry Dalrymple, MD, owner of Parkview Imaging in Santa Monica, Calif, disagrees. He sees Eisenberg “as a kind of leader in the field.” Parkview’s brochure advertises that the $775 whole-body scan is done in “one single and painless visit” using radiation that is “less than that of a conventional CT scan.”

Dalrymple says Parkview advertises “primarily on radio, with a little TV, some Los Angeles Times advertisements, and in doctors’ offices with a regular requisition pad and brochures. It has primed the pump, and now it is mostly word of mouth,” he notes.

Although direct advertising by physicians and medical groups is becoming more commonplace, there is still strong resistance to the practice among many academic clinicians. Stephen J. Swenson, MD, professor and chair of radiology at the Mayo Clinic, Rochester, Minn, is directing a National Institutes of Health study of low-dose CT screening for lung cancer.

“To directly advertise to the public is wrong, and it is wrong because it’s not informed consent,” Swenson says. “When citizens see these ads, they infer that evidence-based medicine has been performed, and that the risks are outweighed by the benefits.

“If [physicians] are advertising directly to patients, and they come in off the street and spend their money [for screening tests], they don’t know that 99% of the lung nodules found will be benign.”

Swenson say he makes a distinction between advertising directly to patients, and patients having conversations with their personal physicians. “That way they are making informed decisions to have the test done.”

With the lack of scientific studies, patients have no evidence such screening tests have value, he says, with one exception. “Mammography is different because it has been proven to save lives.”

Consumers Union’s Lipman agrees. “You can call it unethical, you can call it bottom-line oriented,” Lipman says. “[Advertising] certainly is not for the greater good or the public health. That’s what I’m concerned with.”

Not all screening studies are done with CT. Edward I. Bluth, MD, chairman of radiology at the Ochsner Clinic and Ochsner Foundation Hospital, New Orleans, is using power Doppler ultrasound to screen for carotid artery stenosis. Bluth’s pilot study3 showed results similar to those of mammography, he says, and cost-effectiveness of $47,000 per quality-adjusted-life-year.

“If we can move the expense of dealing with chronic disease from the diagnostic end because we prevent its occurrence, we can save a lot of money,” Bluth says. “The cost of treating stroke is very high, so if we can reduce [the incidence of stroke] by screening those who are at risk, and by changing the risk, we reduce the treatment cost by reducing the risk. By moving in front of the line instead of the back, it should be less expensive.”

The Liability Issue

If there is considerable cost to the patient for screening examinations, there is considerable physician liability associated with these tests. If the patient who is screened is later found to have a tumor that was not detected, the supervising radiologist may be liable.

“If the patient comes in off the street and if there’s no referring physician,” Berlin says, “the radiologist will have to undertake more responsibility than he ordinarily? would if there were a referring physician. For example, let’s say a patient comes in and has a questionable abnormality. Then, if the patient is referred by a physician, it’s very easy for the radiologist to notify the referring physician and say, ‘Here’s the finding, it’s up to you, I’m out of this.’

“Now the radiologist has turned the care of the patient over to him, and he handles it from this point.”

As Berlin notes, all doctors make errors on occasion.

“Whether it’s a CT scan or a mammogram, we can always misread it,” he says. “That’s generic with whatever test we do. Errors occur. We’re going to make errors on screening tests just like we do on regular tests.

“For example, the two CT screening tests that seem to have some mainstream support are heart scans for the calcium [scoring]. The other is lung nodules. You don’t need contrast media for lung nodules, either. However, there is no doubt that if we look at a CT and say, ‘No nodules,’ we’re going to miss some. And the patient comes back 6 months later with a nodule and you’ll look back and say, ‘Oh, my goodness, there it was, I didn’t see it.’ We all make errors.”

Berlin brings up another thorny legal area-the use of contrast agents.

“Probably half the [diagnostic] CT examinations are done with contrast media,” he says. “The reason we use contrast media is there are certain tumors-certain kidney tumors, abdominal tumors, some bone tumors, certain brain tumors-that will only show up if you give the contrast media.

“All of these total-body scans are being done without contrast media. If you don’t use contrast media and you tell a person, ‘You’re fine,’ then 6 months, 12 months later, the patient comes back, and, lo and behold, it’s a kidney cancer. And now you look at the original scan and you say, ‘Well, you didn’t see it because you didn’t use contrast media. If you had used contrast media, you would have seen the tumor.’

“The standard of care is if you’re going to do an abdominal CT, you should use contrast media,” Berlin says. “On the other hand, if you do use contrast media, and the patient has a serious reaction and a disability resulting, then the argument is what was the indication for the contrast media? It was routine. That’s not an indication. So now you’ve breached the standard of care in that regard.”

Long-term Outlook

It took years for Congress to approve screening mammography, and federal legislation is the only way low-dose lung CT screens or whole-body screening will ever be universally covered by Medicare or private insurance. There are a half-dozen scientific studies under way to demonstrate the efficacy of low-dose lung CT screening. The results are so far promising, but inconclusive.

Despite testimonials and TV shows, no one outside the full-body screening business is willing to bet on a Medicare imprimatur for that procedure, or even for low-dose lung CT.

“I don’t think that until you show, as mammography has done, that your procedure will save lives and be cost-effective, that [full-body scanning] will catch on,” Lipman says. “Mammography results in a 30% decrease in the death rate from breast cancer. CT screening for lung cancer has not yet shown that it makes any difference whatsoever in terms of saving lives.”

If lung cancer screening still has years to go before it is accepted by Medicare, approval of full-body scanning is particularly remote. There are no university medical centers doing it in a controlled fashion, and it does not focus on a specific problem, but on multiple organs.

Berlin believes scientific studies for whole-body CT are “really down the road.” “If anything has merit, the lung has merit, and that has a long way to go,” he says. “Consider how long it took to get mammography approved. And that was with the women’s movement. Breast cancer has a certain mystique. It is totally different from everything else.

“[Mammography] has enormous lobbying efforts behind it, and you’re never going to get the lobbying efforts for lung cancer. Plus, with lung cancer, the prognosis is so bad that you have a real argument about early diagnosis-does it really make any difference? Nobody knows. There is some doubt about mammography, but for the most part, the doubt is very minimal. Most people agree that early diagnosis makes a difference in mammography. But there is a lot more controversy about that in lung cancer.

“My own personal opinion is that I don’t think Medicare approval for lung scans will be in our lifetime.”

Robert Bruce is a contributing writer for Decisions in Axis Imaging News.

References:

  1. Bowes P. US doctors offer full body scans. [BBC Web site]. January 2, 2001. Available at: http://news.bbc.co.uk/hi/englis/health/newsid_1097000/1097136.stm. Accessed August 7, 2001.
  2. American College of Radiology. ACR Statement on Total Body CT Screening. Available at://www.acr.org/departments/pub_rel/press_releases/total-bodyCT.html. Accessed August 7, 2001.
  3. Bluth EI, Sunshine JH, Lyons JB, et al. Power Doppler imaging: initial evaluation as a screening examination for carotid artery stenosis. Radiology. 2000;215:791-800.