By John C. Wolf, D.O.
Associate Professor of Family Medicine
Ohio University College of Osteopathic Medicine

HEAVILY ADVERTISED CAT SCANS MAY BE “CAT SCAMS”

Question: In my town there has been heavy advertising for a facility that offers a CAT scan of your lungs for as little as $200. They claim it can detect lung tumors when they’re small enough to be cured. I smoked for many years before I got smart enough to quit about 10 years ago. What are the benefits and risks of these CAT scans for an old smoker like me?

Answer: The scientific evidence clearly shows smoking is bad for one’s health, but you already knew that. Despite this, there are about 45 million Americans who continue to use tobacco products. As you obviously know, lung problems including emphysema, chronic bronchitis and cancer occur much more often in those who smoke. This overall risk is influenced by the amount you have smoked. That is, the number of packs you smoked per day multiplied times the number of years you engaged in this bad habit. This is expressed in pack-years of smoking. Someone with a five pack-year smoking history has a lower risk of these problems than does someone with a 100 pack-year history. Not smoking for a number of years -- like you have wisely done -- will reduce the risk of these disabling and potentially life ending diseases by roughly two-thirds, but it doesn’t reduce that risk back to a never-smoked level.
Recent years have seen major advancements in digital processing and innovations in other related X-ray technologies. This has made it possible to create images of our internal organs that were barely dreamed of a few decades ago. The current version of CT, or CAT scan, equipment makes it possible to obtain detailed images of the lungs and other organs rather quickly, and with a relatively small amount of radiation at a bargain price.
Several years ago facilities in Ohio, as well as in Florida where you live, began to advertise low-cost screening scans that had to be paid for by the patient. The reason he or she must pay is that insurance companies, HMOs, and PPOs don’t pay for “unnecessary” screening exams. That is, exams where no symptoms warrant the test and the general cost of doing the test on many symptomless individuals is considered prohibitively high for the few abnormalities that are found. In fact, some doctors have called this kind of entrepreneurial screening test “CAT scam.”
The risks verses benefits that you asked about are summarized in the simple table below.

As you can see from the relative lengths of the lists, the “Risk” side is substantially longer and two of its items need some additional explanation. Though the radiation dose to perform one chest scan is small, it does increase the risk of cancer, and radiation exposure is cumulative so that subsequent scans add to the cancer risk. A more significant “risk” is the finding of a not-quite-normal area on the study. These subtle abnormalities may be the consequence of scarring from old lung infections, damage from years of smoking, lung tumors of malignant and non-malignant types and many other health problems. These findings not only cause considerable worry for the individual and his or her loved ones, but they necessitate more tests. These obviously increase cost and also may have some associated risks from the tests themselves.
So, I think the smartest choice is to talk to your doctor about your health history, including your concern about lung cancer. Then together you can decide if a CT scan of the lungs or other tests would be helpful. If so, your health insurance will probably pay part or all of the bill, instead of you paying the entire screening test bill out of your own pocket.
And what about the benefit -- finding lung cancer when it is small and curable? Well sure, it does rarely happen that way. The key word here is “rarely.”

"Family Medicine" is a weekly column. To submit questions, write to John C. Wolf, D.O., Ohio University College of Osteopathic Medicine, P.O. Box 110, Athens, Ohio 45701. Past columns are available online at http://www.FamilyMedicineNews.org.