ABCs of lung cancer screening Key information for primary care physicians

Objective To review new evidence reported since the 2016 publication of the Canadian Task Force on Preventive Health Care recommendations and to summarize key facets of lung cancer screening to better equip primary care physicians prior to widespread implementation of the recommendations. Data quality Since 2016, a large new randomized controlled trial and updates to 4 other studies have been published. A search for studies published between 1 January 2004 and 31 December 2020 was performed in PubMed using the English keywords lung cancer screening eligibility, lung cancer screening criteria and lung cancer screening guidelines. All information found in peer-reviewed articles, reference lists, textbooks and websites were considered. Main message Lung cancer diagnosed at stage 4 has a 5-year survival rate of just 5%, and its impact is disproportionately high in low socioeconomic status, rural and indigenous populations. By de-testing, i.e. diagnosing lung cancer at an earlier and more treatable stage, lung cancer screening reduces mortality, with the number of subjects to be screened being 250 to prevent 1 death. We review the practicalities of lung cancer screening, including screening criteria, appropriate screening with low-dose CT scans and management of findings. Screening-related harms, such as overdiagnosis and incidental findings, are discussed to enable primary care physicians to appropriately counsel their patients about the adoption of new lung cancer screening programmes. Conclusion Lung cancer screening, with its emphasis on smoking cessation, is an excellent addition to the primary care physician's prevention toolbox. The implementation of formal and pilot lung cancer screening programs across Canada means that primary care physicians will increasingly have to counsel their patients to accept lung cancer screening.