Published August 17, 2021
Lung cancer is the second most common cause of cancer and is the leading cause of cancer deaths in the United States. Screening for lung cancer in high-risk individuals can prevent deaths. This article will discuss the United States Preventive Services Task Force’s updated screening guidelines for lung cancer and explain pertinent information for the primary care clinician.
The top takeaways:
- Most people are diagnosed with lung cancer at an advanced stage.
- The five-year survival rate for people diagnosed with advanced-stage lung cancer is less than 20%.
- Smoking and advanced age are the most significant risk factors for lung cancer.
- The United States Preventive Services Task Force recommends lung cancer screening with low-dose computed tomography in adults aged 50 to 80 years who have a 20 pack-year smoking history and either currently smoke or quit smoking within the last 15 years.
- Screening with computed tomography should be performed by experienced radiologists or should utilize the Lung-RADS criteria.
- Primary care clinicians need to improve the number of high-risk people who are offered lung cancer screening.
- The primary care clinician must encourage smoking cessation in adults and prevent the initiation of tobacco use in school-aged children and adolescents.
Lung Cancer Facts
In 2021, the American Cancer Society estimates that there will be about 235,000 new lung cancer cases and 131,000 deaths.1 Most people are diagnosed with lung cancer at age 65 or older, and often the diagnosis is made when the disease is advanced.1,2 When lung cancer is detected and localized within the lungs, the five-year survival rate is 56%.2 At an advanced stage, the five-year survival rate is less than 20%.2 Sadly, more than half of people with lung cancer die within one year of being diagnosed.2 Screening people at high risk for lung cancer can decrease deaths since treatment of stage 1 and 2 lung cancer can be curable. Low-dose computed tomography is the recommended screening modality, and it has improved mortality rates by up to 20% among high-risk populations.2
The significant risk factor for lung cancer is smoking. Experts estimate that smoking is responsible for 90% of lung cancer cases.2 However, since the number of people who smoke is declining, the number of new lung cancer cases is also decreasing, but the overall prevalence is still high. The next most significant risk factor is advanced age. Other factors that put people at risk for lung cancer include radon exposure, air pollution, and occupational exposures, including asbestos and coke (an important fuel in iron manufacturing in smelters and foundries).2
The United States Preventive Service Task Force’s Lung Cancer Screening Guidelines
The United States Preventive Service Task Force’s (USPSTF) screening guidelines for lung cancer were last updated in 2013. Previously, they recommended annual low-dose computed tomography (CT) scanning for patients at high risk for the disease, including those aged 55 to 80 years with a previous 30 pack-year smoking history.3 However, the USPSTF updated its recommendations in March of 2021 and focused on the most significant lung cancer risk factors: tobacco use and age. Now high-risk individuals include those aged 50 to 80 years with a pack-year history of 20 pack-years of smoking.3 Screening should continue to be conducted annually in current smokers and people who have quit smoking within 15 years.3 The screening recommendations can be discontinued when a person has not smoked for 15 years or is given a life-limited diagnosis for which treatment for lung cancer would not improve the overall life expectancy.3 View the recommendation here.
Low-dose Computed Tomography Use for Lung Cancer Screening
The USPSTF systematic review of the evidence found that low-dose computed tomography (CT) has high sensitivity and moderate specificity for diagnosing lung cancer, especially if the diagnostic imaging is performed at academic centers with experienced lung cancer diagnostic radiologists or according to the American College of Radiology Lung Imaging Reporting and Data System (Lung-RADS) classification criteria.3 Using this radiology classification system helps to reduce false-positive results that can lead to unnecessary testing, invasive procedures, overdiagnosis, and patient anxiety. One study estimated that using the Lung-RADS criteria would have prevented approximately 23% of unnecessary invasive procedures implemented due to false-positive results.4 Other lung screening modalities, including sputum cytology, chest radiography, and biomarker testing, are not recommended.
Lung Cancer Screening Utilization
The USPSTF also evaluated the utilization of lung cancer screening, and a study of 10 states found that only 14% of eligible high-risk patients were screened in the prior 12 months.5 It is essential that educators and experts adequately promote lung cancer screening. The primary care clinician must understand and use these guidelines for them to truly be effective.
Lung Cancer Prevention
However, the best way to save lives from lung cancer is to encourage smoking cessation. In January 2021, the USPSTF reaffirmed its smoking cessation in adults recommendation, and experts advise that clinicians ask all adults about tobacco use. Primary care clinicians should provide behavioral interventions and the U.S. Food and Drug Administration (FDA) approved pharmacotherapy for tobacco cessation.6 Additionally, in April 2020, the USPSTF reaffirmed its recommendation on primary care interventions in children and adolescents to prevent tobacco use. Primary care clinicians should provide interventions like education and brief counseling to prevent the initiation of tobacco use by school-age children and adolescents.7
Other organizations continue to maintain lung cancer screening guidelines, but they are more similar to the USPSTF’s 2013 recommendation instead of the 2021 recommendation. View the different recommendations in the table below.3,8
Organization | Guidelines/Recommendations | Year |
United States Preventive Services Task Force | Annual low-dose CT scan screening for high-risk individuals (ages 50 to 80 years with a 20 pack-year history of smoking and current smoker or quit within past 15 years). Discontinue when the person has not smoked for 15 years or if limited life expectancy. | 2021 |
American Association of Thoracic Surgery | Annual low-dose CT scan screening for high-risk individuals (ages 55 to 79 years with ≥30 pack-year history of smoking and current smoker or quit within past 15 years; ages 50 to 79 years with ≥20 pack-year history and cumulative risk >5% over next 5 years; or lung cancer survivors with no incidence of disease for ≥4 years). | 2012 |
American Cancer Society | Annual low-dose CT scan screening for high-risk individuals (ages 55 to 74 years with ≥30 pack-year history of smoking and current smoker or quit within past 15 years). | 2013 |
American College of Chest Physicians | Annual low-dose CT scan screening for high-risk individuals (ages 55 to 77 years with ≥30 pack-year history of smoking and current smoker or quit within past 15 years). | 2018 |
National Comprehensive Cancer Network | Annual low-dose CT scan screening for high-risk individuals (ages 55 to 74 years with ≥30 pack-year history of smoking or if no longer smoking, smoking cessation within 15 years, or age ≥50 years with a ≥20 pack-year history of smoking with 1 additional risk factor like a personal history of cancer or lung disease, family history of lung cancer, radon exposure, and occupational exposure to carcinogens.). | 2018 |
Learn more about the USPSTF lung cancer screening guidelines from Dr. Frank Domino at Pri-Med.
References
1. American Cancer Society. Key statistics for lung cancer. Accessed May 22, 2021. https://www.cancer.org/cancer/lung-cancer/about/key-statistics.html
2. American Lung Association. Lung cancer fact sheet. Accessed May 22, 2021. https://www.lung.org/lung-health-diseases/lung-disease-lookup/lung-cancer/resource-library/lung-cancer-fact-sheet
3. US Preventive Services Task Force. Screening for Lung Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;325(10):962–970.
4. Pinsky PF, Gierada DS, Black W, et al. Performance of Lung-RADS in the National Lung Screening Trial: a retrospective assessment. Ann Intern Med. 2015;162(7):485-491.
5. Zahnd WE, Eberth JM. Lung cancer screening utilization: a behavioral risk factor surveillance system analysis. Am J Prev Med. 2019;57(2):250-255.
6. US Preventive Services Task Force. Interventions for Tobacco Smoking Cessation in Adults, Including Pregnant Persons: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;325(3):265–279.
7. US Preventive Services Task Force. Primary Care Interventions for Prevention and Cessation of Tobacco Use in Children and Adolescents: US Preventive Services Task Force Recommendation Statement. JAMA. 2020;323(16):1590–1598.
8. Deffebach ME, Humphrey L. Screening for lung cancer. Post TW, ed. UpToDate. UpToDate Inc. Accessed May 22, 2021. https://www.uptodate.com/contents/screening-for-lung-cancer