For doctors at Anne Arundel Medical Center, the common-sense idea was too good to pass up: offer habitual smokers a low-cost CT scan to see if cancer has taken root in their lungs.
CT scans can spot lung nodules as small as a grain of rice. Lung cancer, the deadliest of all cancers, is often caught too late to be cured, long after the first symptoms have appeared.
"If you find [lung cancer] earlier and smaller, you have a better chance of curing it," said Dr. Kenneth Adam Lee, the hospital's chief of thoracic surgery. "This gives us a chance to do some good for these people."
Yet, as with other instances in which medical intuition has led doctors down questionable paths, the notion that finding lung cancer earlier will lead to better outcomes for patients is at the center of a major debate. Insurance companies do not cover lung cancer screening, because no one has proved that it saves lives. No major medical society advocates the practice.
Instead, many doctors argue that screening even the lungs of habitual smokers can lead to unnecessary - and sometimes dangerous - follow-up tests that can harm or even kill patients. Others argue that abnormalities turned up by screenings might be so minor that patients could die of something else before they even realize that they have slow-growing lung cancer.
What lung screening proves, they say, is that the more you look, the more you find, not that there's a lot of value in the results.
"I'm well aware that there is enthusiasm in at least some sectors" for lung screening, said Dr. Barnett S. Kramer, associate director for disease prevention at the National Institutes of Health. "But the evidence doesn't support it. It seems so intuitive that it ought to work. But the history of medicine tells us that even highly intuitive notions that something must be beneficial can be harmful."
Consider hormone replacement therapy (HRT), long employed to ease the symptoms of menopause and widely assumed to help stave off aging by supplying female hormones that the body has stopped making. Many doctors believed that boosting estrogen levels would also ward off heart disease and osteoporosis. But a major study showed that, for many women, HRT could cause more harm than good - including increasing their risk of heart attack.
