Lung cancer risk increased for smokers not offered annual screening

Smokers for whom annual screening with low-dose computed tomography (LDCT) is not recommended may have a high risk for lung cancer, according to a study published online July 28 in JAMA Oncology.

Charles Faselis, M.D., from the Veterans Affairs Medical Center in Washington, D.C., and colleagues examined the risk for lung cancer in older smokers for whom LDCT screening is not recommended using data from 4,279 individuals aged 65 years and older. Incident lung cancer was assessed during a median of 13.3 years of follow-up.

The researchers found that incident lung cancer occurred in 0.5, 5.0, and 5.0 percent of 1,973 never smokers, 100 current smokers with less than 20 pack-years of smoking, and 516 former smokers with 20 or more pack-years of smoking with 15 or more years of smoking cessation. The cause-specific hazard ratios for incident lung cancer in the two groups for whom LDCT is not recommended were 10.54 and 11.19 for current nonheavy smokers and for former smokers with less than 15 years of smoking cessation, respectively, compared with never smokers. After adjustment for age, sex, and race, the hazard ratios were 10.06 and 10.22, respectively.

"These findings suggest that future studies should determine whether annual LDCT screening could reduce lung cancer mortality in these smokers," the authors write. "Future studies should also include development of machine learning and/or artificial intelligence algorithms to identify high-risk subsets of these smokers to optimize the risk-benefit ratio of such screening."