A recently published study in The Journal of the American Medical Association compared two lung screening strategies in older smokers, and concluded that evaluating individualized lung cancer risk when determining screening eligibility might be significantly more efficient and effective than recommending screening to all smokers in a given sample.
The US Preventive Services Task Force (USPSTF) has advised that all smokers 55-80 years old with at least 30-pack years of smoking and all former smokers 55-77 years old with no more than 15 years since quitting undergo computed tomography (CT) lung cancer screening in order to prevent lung cancer deaths. In a new study published in The Journal of the American Medical Association, researchers noted there is an absence of lung cancer risk tools that have been validated using representative US population samples, and there is insufficient research evidence supporting individual risk-based lung cancer in the US. Thus, they conducted this study with the aim of comparing the outcomes from individual risk-based CT lung cancer methods (which suggest screening for select individuals at highest risk of lung cancer, who coincidentally do not fall under USPDTF guidelines) and the screening recommendations provided by the USPSTF (which groups at-risk individuals in different subgroups based on criteria like age and number of smoking years). Existing data from the following American lung cancer screening trials was consulted: The Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial, and the NLST (National Lung Screening Trial). In addition to those trials, some data from the National Health Interview Survey was also used.
When compared with a model based on the above mentioned USPSTF recommendations, the authors found that an individual risk-based model for CT lung cancer screening was associated with an increase of prevented lung cancer deaths during a 5 year period. Additionally, their results estimated that an individual risk-based model was linked to an improved screening effectiveness: the model decreased the NNS (number needed to screen) to prevent 1 lung cancer death. According to USPTF screening recommendations, an estimated 9.0 million US smokers would be eligible for lung cancer screening; relatedly, the USPTF model estimated 46,488 deaths caused by lung cancer were capable of being avoided via screening. Interestingly, individual risk-based selection screening in the same amount of smokers (9.0 million) was estimated to successfully prevent 20 % more deaths. As well, individual risk-based selection screening comes with more efficiency, reducing the number of false-positives seen in USPSTF recommendations.
Presently, most deaths caused by lung cancer are not screen preventable. Quitting is the only truly effective preventive measure against lung cancer smokers can take.
Written By: Melissa Booker