A study by Vanderbilt researchers that analyzed both smoking history and genetic risk variants for lung cancer supports modifying current guidelines to include additional smokers for lung cancer screening.
The study, published Feb. 26 in Carcinogenesis, also suggests that genetic risks identified in genome-wide association studies (GWAS) could be considered to further identify which smokers should undergo lung screens at an earlier age.
The analysis supports the recent recommendation by the U.S. Preventive Services Task to lower the screening age from 55 to 50 and to reduce the number of smoking history pack years from 30 to 20. The recommendation is partially based on a study by Vanderbilt researchers published in JAMA Oncology that revealed a striking racial disparity for eligibility under the existing guidelines — among smokers diagnosed with lung cancer, only 32% of African Americans versus 56% of whites were eligible for screening.
The new research published in Carcinogenesis indicates that lowering the age threshold will also benefit whites with high genetic risks for lung cancer. Wei Zheng, MD, PhD, the Anne Potter Wilson Professor of Medicine and director of the Vanderbilt Epidemiology Center, and colleagues incorporated a polygenic risk score they developed using GWAS-identified risk variants for lung cancer in the analysis of data from the UK Biobank, which collected data and biospecimens from approximately 500,000 people aged 40-69 from England, Scotland and Wales. The analysis showed that current smokers with a 20 to 29 pack-year smoking history and a high polygenic risk score reached the risk threshold for lung cancer screening at age 50.
“This study supports the use of both smoking history and genetic biomarkers to identify high-risk smokers for designing a cost-effective lung cancer screening program” said Zheng.
The lead author Guochong Jia, MPH, was also the lead author of a previous study that constructed the polygenic risk scores. That research, published last year in JNCI Cancer Spectrum, developed polygenic risk scores for eight common cancers and concluded they could potentially be used for personalized risk assessments.
Other authors of the study most recently published in Carcinogenesis are Wanqing Wen, research associate professor of Medicine; Pierre Massion, MD, Cornelius Vanderbilt Chair in Medicine; and Xiao-Ou Shu, Ingram Professor of Cancer Research.