Special Screening for Lung Cancer Seems Worthwhile
July 9, 2001 -- A tool for screening the lungs of people who smoke or used to smoke appears to be a useful way of picking up lung cancer in its early stages. The tool is called a computed tomography, or CT, scan, which helps doctors look inside the lungs, a little bit like an X-ray. Hopefully, these early diagnoses will lead to better survival rates for those afflicted with the disease.
"Lung is the deadliest cancer, killing more men and women than the [other] top three combined," study author Claudia I. Henschke, MD, PhD, tells WebMD. She is a professor of radiology at Weill Medical College of Cornell University and division chief of chest imaging at the New York Presbyterian Hospital, both in New York City
"This continues the landmark research ... showing that there's great promise for lung cancer screening," says expert Arnold J. Rotter, MD. The best analogy is our experience with mammography [in which] ... it's proper to find two to four cancers per thousand screens. Here, they found seven out of 1,100." Rotter is a diagnostic radiologist and director of CT scanning at City of Hope Medical Center in Duarte, Calif. He was not involved in the research.
"Based on our results," says Henschke, "it seems that CT screening is highly effective and cost-effective for smokers and former smokers aged 60 and over. You can extrapolate and say that [it would probably also be helpful] to screen people of lower ages."
In fact, at her institution, they screen anyone starting at age 40 who has smoked for 20 years or more.
"For smokers, they should stop smoking, but clearly a lot of them are not going to do that," Rotter tells WebMD. "So I think lung cancer screening [with CT] is the way to go ... because there is no effective treatment for lung cancer in anything but the earliest stages. This and all the other studies show that [CT scans] pick up stage I [lung cancers] in about 80% of the patients. For patients to get lung cancer screening, it's probably best to do it in the context of a study to be on top of the latest understandings of this."
Once a year, starting in 1993, Henschke and her colleagues CT scanned the lungs of 1,000 people aged 60 and over who were smokers or former smokers who had smoked for many years. According to Henschke, they found that "not only is the screening test very sensitive, that is it picks up small things really well, but it also has very few false positives, [or positive results that turn out to be negative]." The research is published in the July 2001 issue of the medical journal Cancer.
According to Rotter, "the major critique from the internal medicine people and the National Cancer Institute and the like [about CT screening for lung cancer] is that they're not convinced that early [treatment of lung cancer] will actually save lives. ... [To know that], you need to get hundreds of thousands of cancers and follow them over several years. But our experience with every other cancer is that if you find it early, you make a difference in [survival rates]. I don't think it will be any different for lung cancer. ... If we wait until we dot all the i's and cross all the t's, [we'll miss] thousands of people who could have been saved by catching things early."
For their part, Henschke and her colleagues are following up their patients to see how the CT lung cancer screening will affect their risk of dying of lung cancer.