Published online in advance in NEJM this week, The National Lung Screening Trial Research Team presents findings from a study of the associations between reduced lung cancer mortality and low-dose computed tomographic screening. So far, the use of screening has been ineffective against the mortality rate in lung cancer, the authors write. But studies on low-dose helical computed tomography show that the technology can detect many early-stage lung tumors. In this study, the researchers randomly assigned 53,454 people at high risk for lung cancer into two groups, one of which received three annual screenings with low-dose CT, and the other of which received three screenings with single-view posteroanterior chest radiography. The team found that low-dose CT had a positive screening test rate of 24.2 percent, compared with 6.9 percent for radiography. There were 247 deaths from lung cancer per 100,000 people in the CT group, and 309 deaths per 100,000 people in the radiography group, the authors write, representing a relative reduction in mortality from lung cancer of 20 percent with low-dose CT screening. "Screening with the use of low-dose CT reduces mortality from lung cancer," they add.
And in an editorial in NEJM this week, the Robert Wood Johnson Foundation's Harold Sox says its time for policy makers to pay attention to new studies on screening for lung cancer. Recent studies have shown that low-dose CT screening is helping to catch lung cancer earlier and has an effect on lung cancer mortality, Sox says. So how should policy makers, who are responsible for drafting screening guidelines and deciding insurance coverage, respond? "Policymakers should wait for cost-effectiveness analyses of the NLST data, further follow-up data to determine the amount of overdiagnosis in the NLST, and, perhaps, identification of biologic markers of cancers that do not progress," Sox says. "Modeling should provide estimates of the effect of longer periods of annual screening and the effect of better adherence to screening and diagnostic evaluation. Systematic reviews that include other, smaller lung-cancer screening trials will provide an overview of the entire body of evidence. Finally, it may be possible to define subgroups of smokers who are at higher or lower risk for lung cancer and tailor the screening strategy accordingly." Patients at risk for lung cancer and their physicians should inform themselves of the advantages and disadvantages of new screening methods, he adds.