The American Lung Association (ALA) recently released new guidelines for lung cancer screening, recommending low-dose computed tomography screening in certain people. The recommendations are based on existing evidence, and in particular the recent results of the National Lung Cancer Screening Trial.
The new ALA guidelines state that individuals who are current or former smokers, aged 55 to 74 years, with a smoking history of at least 30 pack-years (one pack per day for 30 years), and with no history of lung cancer should be screened. The group emphasized that only CT scans should be used, and not chest x-rays.
“Never starting smoking and quitting smoking still remains the best way to prevent lung cancer,” said Norman H. Edelman, MD, the chief medical officer of the ALA, in a press release. He added that home testing for radon is another simple way to reduce the risk of lung cancer. The ALA’s full report on screening was led by Jonathan M. Samet, MD, of the Keck School of Medicine at the University of Southern California.
Lung cancer screening remains controversial, even after the results of the National Lung Screening Trial (NLST) were published last summer. That study included 53,454 high-risk individuals and compared CT scans to chest x-rays. CT scanning lowered mortality due to lung cancer, as well as from any cause, by 20.0% compared with radiography. There were, however, high rates of false positives in both the CT group (96.4%) and the radiography group (94.5%).
In an editorial published along with the NSLT results in the New England Journal of Medicine, Harold C. Sox, MD, of Dartmouth Medical School, wrote that “Policymakers should wait for cost-effectiveness analyses of the NLST data. The findings of the NLST regarding lung-cancer mortality signal the beginning of the end of one era of research on lung-cancer screening and the start of another. The focus will shift to informing the difficult patient-centered and policy decisions that are yet to come.”
The United States Preventive Services Task Force still does not recommend for or against lung cancer screening, citing insufficient evidence. Research is also ongoing into methods beyond CT scans and radiography, including the use of an antibody test in a large trial in Scotland.
Among the other recommendations in the ALA report are some of the logistics of screening large populations for lung cancer. For example, patients should be referred only to centers that have experience with low-dose CT scans and that have multidisciplinary teams capable of comprehensive follow-up to the screens. It is also important that CT scans are not offered to everyone, and that ethical policies for publicizing screening services are established.