Lung cancer is the leading cause of mortality and person-years of life lost from cancer among US men and women. Early detection has been shown to be associated with reduced lung cancer mortality. Our objective was to update the American Cancer Society (ACS) 2013 lung cancer screening (LCS) guideline for adults at high risk for lung cancer. The guideline is intended to provide guidance for screening to health care providers and their patients who are at high risk for lung cancer due to a history of smoking. The ACS Guideline Development Group (GDG) utilized a systematic review of the LCS literature commissioned for the US Preventive Services Task Force 2021 LCS recommendation update; a second systematic review of lung cancer risk associated with years since quitting smoking (YSQ); literature published since 2021; two Cancer Intervention and Surveillance Modeling Network-validated lung cancer models to assess the benefits and harms of screening; an epidemiologic and modeling analysis examining the effect of YSQ and aging on lung cancer risk; and an updated analysis of benefit-to-radiation-risk ratios from LCS and follow-up examinations. The GDG also examined disease burden data from the National Cancer Institute’s Surveillance, Epidemiology, and End Results program. Formulation of recommendations was based on the quality of the evidence and judgment (incorporating values and preferences) about the balance of benefits and harms. The GDG judged that the overall evidence was moderate and sufficient to support a strong recommendation for screening individuals who meet the eligibility criteria. LCS in men and women aged 50–80 years is associated with a reduction in lung cancer deaths across a range of study designs, and inferential evidence supports LCS for men and women older than 80 years who are in good health. The ACS recommends annual LCS with low-dose computed tomography for asymptomatic individuals aged 50–80 years who currently smoke or formerly smoked and have a ≥20 pack-year smoking history (strong recommendation, moderate quality of evidence). Before the decision is made to initiate LCS, individuals should engage in a shared decision-making discussion with a qualified health professional. For individuals who formerly smoked, the number of YSQ is not an eligibility criterion to begin or to stop screening. Individuals who currently smoke should receive counseling to quit and be connected to cessation resources. Individuals with comorbid conditions that substantially limit life expectancy should not be screened. These recommendations should be considered by health care providers and adults at high risk for lung cancer in discussions about LCS. If fully implemented, these recommendations have a high likelihood of significantly reducing death and suffering from lung cancer in the United States.
INTRODUCTION
In 1980, the American Cancer Society (ACS) withdrew a prior recommendation for regular lung cancer screening (LCS) with chest radiography (CXR) in persons who currently or formerly smoked because a series of randomized controlled trials (RCTs) conducted in the 1970s had not demonstrated convincing evidence that LCS saved lives.1 Thirty-three years later, after publication of the National Lung Screening Trial (NLST) (ClinicalTrials.gov identifier NCT00047385) demonstrating that three rounds of annual LCS with low-dose computed tomography (LDCT) were associated with a 20% relative mortality reduction compared with annual LCS with CXR,2 the ACS issued a recommendation for annual screening with LDCT in adults who met the eligibility requirement for the NLST (i.e., individuals aged 55–74 years with a 30 or greater pack-year history of smoking who currently smoke, or formerly smoked and had not exceeded 15 years since smoking cessation, and did not have life-limiting comorbidity).3 In this update of the 2013 LCS guideline, the ACS Guideline Development Group (GDG) addresses a broad spectrum of issues related to LCS, including the most recent evidence on the efficacy and effectiveness of LCS, the lung cancer risk in persons who formerly smoked and have exceeded 15 years since cessation, estimates of the benefits and harms of screening past age 80 years and screening in eligible adults with greater than 5 years of longevity, and updated benefit-to-radiation-risk ratios based on modern doses from ionizing radiation from screening and follow-up examinations. We also discuss the challenges of implementing LCS, enduring disparities in disease burden and screening rates, and the urgent need to significantly improve utilization and adherence to screening and follow-up testing among qualifying individuals.
In this update of LCS, the ACS recommends that individuals aged 50–80 years who currently smoke or who formerly smoked and are at high risk for lung cancer because of a 20 or greater pack-year history of cigarette smoking undergo annual LCS with LDCT (Tables 1 and 2). We also recommend against using any duration of years since quitting smoking (YSQ) as a criterion to begin or end LCS in individuals who formerly smoked and who meet age and pack-year eligibility criteria. Individuals who smoke should be advised to quit and offered evidence-based smoking-cessation interventions. Existing comorbid conditions that may limit life expectancy or the inability or unwillingness to undergo evaluation of positive screening findings or to undergo treatment are factors that should preclude referrals for screening. Because of these considerations, the risks associated with LCS, and the relative newness of LCS to the target population, potentially eligible individuals should undergo a process of shared decision-making (SDM) that includes a discussion about the purpose of LCS, the consensus among leading organizations on recommendations endorsing LCS; the screening process and the importance of regular screening; the benefits, limitations, and potential harms of screening; and consideration of patient values and preferences. We also discuss the challenges of implementing LCS, enduring disparities in disease burden and screening rates, and the urgent need to significantly improve utilization and adherence to screening and follow-up testing among qualifying individuals. This guideline for LCS is based on the underlying burden of disease, an assessment of the strength of evidence, the balance of benefits and harms, and consideration of patient values and preferences.
| These recommendations represent updated guidance from the American Cancer Society for asymptomatic persons who are at high risk of lung cancer based on cumulative exposure to tobacco by smoking. |
| Recommendation |
| The American Cancer Society recommends annual screening for lung cancer with low-dose computed tomography in asymptomatic individuals aged 50 to 80 years who currently smoke or formerly smoked and have a ≥20 pack-yeara smoking history (strong recommendation b; moderate quality evidence). |