Stemming the Craze on CT Scans

In medicine, not everything that makes sense is sensible. Because smoking predisposes to lung cancer, and because advanced lung cancer is incurable, it seems to make sense to screen all smokers for early cancers and treat them while they are treatable. And because coronary disease is common, it seems to make sense to screen middle-age people so some preventative measure can be taken before a heart attack strikes them down.

The wide availability of ultrasensitive CT scans makes such screening possible, and two groups are promoting the tests. Yet the medical establishment disagrees. Why?

One proposal, the Screening for Heart Attack Prevention and Education guidelines, was issued in 2006 by an independent, self-selected group of cardiologists. By screening, the group’s spokesman said, 90,000 deaths could be prevented and billions of dollars saved.

Around the same time, a self-selected consortium of radiologists called the International Early Lung Cancer Action Program published an uncontrolled study of early detection in which it claimed to cure more than 90{06cf2b9696b159f874511d23dbc893eb1ac83014175ed30550cfff22781411e5} of lung cancers, an astonishing rate.

Despite these claims and observations, major professional organizations did not go along with the recommendations of these two groups. The American Heart Assoc., the American College of Cardiology, the American College of Chest Physicians, and the American Cancer Society, among others, had examined the evidence on screening, and had identified its well-known problems.

Studies such as the early lung cancer program were uncontrolled; screening often detects lesions that may never become clinically important; many discovered abnormalities, especially spots on the lung, are not cancers; and many patients end up having to undergo invasive procedures when some abnormality is found even when the finding is insignificant in terms of the patient’s ultimate well-being.

Both the Screening for Heart Attack Prevention and Education group and the International Early Lung Cancer Action Program were undeterred.

The heart attack prevention group’s investigators and their collaborators in the so-called Assoc. for Eradication of Heart Attack convinced a Texas state representative to introduce legislation that would mandate reimbursement for tests to detect asymptomatic arteriosclerosis. The lung cancer group investigators and their collaborators in the so-called Lung Cancer Alliance went further.

They not only called for payment for CT-guided screening of smokers, but they declared publicly that the ongoing controlled, blinded clinical trial of screening centered at the National Institutes of Health was unethical. They complained to Elias Zerhouni, the head of the NIH, and they stirred up the leadership of the House Committee on Energy and Commerce to investigate the principal investigators of the NIH study for alleged financial conflicts, accusations that proved unfounded.

Why all the fuss? Why were the organizations pushing so hard, not only bucking the recommendations of major organizations, but going directly to legislatures to get their policies implemented? Why not go through the usual channels in their own professional organizations, offering their evidence and opinion and getting the official policies changed? Perhaps they were true believers, convinced that their interpretation of the evidence would provide a great benefit for humanity, and impatient with the sluggishness of the big professional societies as well as the snail’s pace by which physicians often change their practices. Perhaps.

But given the expansion of privately owned CT scanners in the country, and the possibility of a reimbursement bonanza for such procedures, another, more sinister explanation is possible, namely a profit motive. Such a motive became more credible when Paul Goldberg, a reporter who covers the cancer field, found that the two lead investigators of the lung cancer study held 27 patents on procedures for CT screening and lung biopsy procedures. Information also surfaced that the heart attack prevention guidelines were sponsored by Pfizer, a company likely to benefit from the use of its drugs if extensive cardiac screening were implemented.

How do we know whether these screening recommendations are motivated by concern for patients’ welfare or money, or perhaps both? We don’t. But widespread screening for lung cancer and heart disease can be risky and will be expensive.

Experience shows that every time we approve a screening procedure, it is used more widely than the indications for which it was originally approved. More screening machines invariably lead to more tests; more tests yield more false positive results, more risk to screened patients, and more expense.

Testing decisions must be made by organizations that sort through all the evidence. They must appoint guideline committees that are not influenced by how much their colleagues make or how many pills the companies sell that pay them to speak or consult. We are nearly at the limit of our expenditures on medical care; we don’t need more expenses for tests that have been tainted by possible financial bias. We must remember who will pay for all these additional tests: you and me.

Dr. Jerome P. Kassirer is a professor at Tufts University School of Medicine. This article first appeared in the Boston Globe.

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