Background: Lung cancer (LC) is the second most common malignant tumor worldwide, with 2.21 million new cases, and the leading cause of cancer-related deaths, with 1.8 million deaths worldwide; 12% of all new cancer cases are LC. Tobacco use is one of the main risk factors associated with the development of LC. Despite smoking being the main component of the criteria for selecting the population at high risk for developing LC, the history of pack-years smoked alone is an imperfect and biased measure of cumulative tobacco exposure. There is evidence that using only pack-years to determine eligibility for LCS, as outlined in the current guideline of the United States Preventive Services Task Force (USPSTF), has inadvertently excluded many high-risk individuals, especially those from racial and ethnic minority groups. In Brazil, LCS is not currently recommended, despite national and international studies indicating that low-dose computed tomography (LDCT) is a viable strategy, even in areas with a high incidence of tuberculosis (TB).
Objectives: To analyze the smoking patterns in terms of intensity, duration, and cessation in the Brazilian population, using the National Health Survey (PNS), by race, and to identify the distribution of race across different LCS Criteria.
Methods: Analytical retrospective study, based on the application of lung cancer screening selection criteria to the Brazilian population with a history of smoking (current and former smokers), using data from the 2019 National Health Survey (PNS).
Results: The National Health Survey (PNS) shows that Black and mixed-race individuals present slightly higher proportions of smokers with a smoking history of 20 years or more (77.6% and 76.7%, respectively), when compared to white individuals (73.0%) (p < 0.001). However, a smoking history of ≥ 20 pack-years, a classic criterion for eligibility in LCS, did not show significant differences between the groups, although there is statistical significance (p < 0.001). This finding reinforces the importance of considering not only smoking intensity but also duration and time since cessation in risk stratification. Additionally, a cessation time of ≤ 15 years is more frequent among Black and mixed-race individuals, suggesting possible accumulated vulnerability, since individuals with shorter abstinence times still present a high LC risk.
When applying the current USPSTF criteria of age, smoking history of ≥ 20 pack-years, and less than 15 cessation time, among non-white individuals, the proportion eligible for the LCS is 30%; 39% when cessation is removed. When pack-years is replaced by smoking duration, the eligibility is 56% and 77%, considering only the smoking duration. Among White individuals, the USPSTF criteria yield 30% of eligible individuals and 42% when cessation is removed. Using smoking duration instead of pack-years, the percentages are 50% and 73% using only smoking duration without cessation.
Conclusion/Implications: The most restrictive LCS criteria is the one that combines age, pack-years, and time since cessation. Changing pack-years to smoking duration increases the number of people included in the screening; however, the most comprehensive and inclusive criteria would be to consider only smoking duration greater than 20 years, excluding time since cessation.

Distribution of smoking characteristics: duration (3A and 3D), cigarettes per day (3B and 3E) and pack-years (3C and 3F) of smokers and ex-smokers over 50 years of age, according to white/non-white and cessation time less than 15 years (3D, 3E and 3F). Br