Why Whole Body Scans Are A Bad Idea
"Why wait for symptoms
to occur?" The radio ad is pitching the latest example of how
entrepreneurial America's medical care system has become.
Whole-body scans are now advertised to healthy people along with the idea
that finding disease early can be nothing but beneficial.
The use of scanners to screen people for heart disease and cancer before the
appearance of symptoms is relatively new. Until the last few years, such
expensive, high-tech equipment was reserved solely for diagnosis-as the
last-resort, state-of-the-art method for diagnosing people whose symptoms
require further investigation. This has begun to change dramatically with a
trend that started on the West Coast. Centers with names like AmeriScan and
Imaging for Life have opened in large cities. Their popularity got a major
boost when Oprah Winfrey enthusiastically described her own whole-body scan
experience on national TV last year.
Billed as a "high-tech medical check-up," the scans are costly, ranging from
about $300 for a lung scan to $1,000 for the whole body. People typically go
for scanning without a doctor's recommendation; and they usually pay out of
pocket, as most insurance companies do not cover these tests. And rightly
so. The use of scanners as screening tests is a bad idea for two reasons:
false alarms and too much radiation. This article will explore radiation
risk only because many past issues of Dr. M's Senior Health Tips have addressed other harms
caused by screening, including unnecessary biopsies, unnecessary cancer
treatment, and false reassurance. Many organs of the body, most notably, the
breast and prostate, harbor small cancers that would safely remained dormant
had they never been discovered and surgically removed. Similar concerns
about overtreatment apply to finding blockages in the coronary arteries of
CT scans involve much higher doses of radiation than standard x-rays because
they provide three-dimensional, multiple "slices" of the body. A CT chest
scan, for example, involves about 400 times the radiation dose of a single
chest x-ray. A CT scan of the abdomen or pelvis involves a radiation dose
500 times that of a chest x-ray. The 2000 European Commission
Directorate-General for the Environment reported these dose estimates based
on surveys of diagnostic medical tests conducted at hundreds of hospitals in
There is no equivalent U.S. agency that provides similar effective-dose
guidelines for tests involving radiation exposure. Nor do we have an
independent agency that regulates the use of CT scanners. The consumer is
left with the radiologist's word regarding low-dose equipment claims. There
is no inspection of these scanning centers as there is for mammography
facilities, which are regulated by the Food and Drug Administration. The FDA
sends warning letters to the mammography facilities whose equipment is found
to emit higher than necessary radiation and shuts down any facility whose
equipment is known to emit excessively high radiation.
All x-ray and scanning facilities should get this kind of oversight, but
they don't. The FDA is currently considering the issue of regulation,
according to Thomas B. Shope, Jr., PhD, of the FDA's Center for Devices and
Radiological Health. In a telephone interview, Dr. Shope said that
radiologists at these new scanning centers are, in effect, selling a service
that is "off label," which means that CT scans are intended for diagnostic
purposes but not for screening symptomless people. Furthermore, there is no
requirement for the manufacturers to prove their equipment is safe and
effective for this new use. All scanners are "grandfathered" because the
original CT scanning equipment came on the market before 1976, when the FDA
first began requiring proof of safety and efficacy for medical devices.
As a result, the new scanners with their purported improvements of high
resolution and low-dosage are merely cleared by the FDA, as opposed to
approved. The latter entails a more rigorous review to prove safety and
efficacy, which is similar to that required of a new drug or medical device.
To receive FDA clearance, Dr. Shope explained, the equipment manufacturers
merely had to show that their machines are equivalent to the older CT
scanner in dose and image quality.
Much more rigorous FDA oversight is long overdue. Last year, a small survey
of hospitals in the Midwest showed that children undergoing CT scans were
exposed to adult doses of radiation that were higher than necessary to
produce good image quality.
The scanning centers are allowed to get away with misleading advertising. As
things stand now, the FDA cannot challenge even the most obvious erroneous
claim, unless the equipment brand and model number is identified in the ad.
All a scanning center has to do is avoid mention of this information, and
they are free to mislead us all they want.