Know Benefits, Risks of Total-Body CT Scans
A growing number of public health officials believe a popular health-screening exam is being overused. They say using a full-body computed tomography exam, or CT scan, as an early disease-detection procedure may actually increase health risks and possibly have other negative consequences.
Nancy Major, M.D., a radiologist at Duke University Medical Center, says the scans combine X-rays and computer technology to produce sharp, two-dimensional internal images. She points to several factors that have helped dramatically increase the procedure's popularity in the past several years.
"The increase in total-body scanning has been driven by the increased speed of the study and the improved quality of the images," says Major, who specializes in musculo-skeletal imaging at Duke. "You can now get results in just a few minutes and see detail of areas that may be abnormal at far greater definition. These two factors, plus the efforts of some very entrepreneurial radiologists, have really pushed the idea of total-body scanning as a way to evaluate your health."
Even though a scanning facility may be in a convenient location and the scan may only take a few minutes, Major says consumers need to be educated about the potential downsides of voluntary total-body scanning, which can subject the body to far greater levels of radiation than a standard X-ray.
"If you're feeling well and have no symptoms of disease, you probably don't want to expose yourself to radiation therapy unnecessarily," she says. "There are some very sensitive organs that would be getting exposed to this X-ray: the thyroid gland, the lens of your eye, gonadal tissue, just to name a few that are very radio-sensitive.
"The other important issue is for patients to know that the information they're given at the end of the studies may not alter what will ultimately happen to them. For example, a patient may have a tumor that's resolved in the kidney that turns out to be malignant. She goes through surgery and has a reasonable outcome, surviving at five years. The outcome may be exactly the same as if she had waited until she became symptomatic for that cancer. The comparative studies on this simply have not yet been done, to say that the outcome for the patient is going to change by having this done ahead of time.
"The other example is identifying something that's there but may be of a completely benign process. It's an unnecessary out-of-pocket expense, since it would not be covered by insurance," Major adds. "Then you've got dollars for follow-up studies on top of that, visits to the doctor's office, and a lot of anxiety. And sometimes what they find, you could have lived with forever and not have had to spend a cent."
Major says doing a full-body CT scan on someone with no symptoms of disease is, in effect, selling peace of mind, usually to affluent consumers and at a steep price. She recommends not having a full-body CT scan unless it's ordered by a physician.