New Horizons in Lung Cancer Screening

Cancer is the second leading  cause of death in the United States, following only heart disease [1, 2]. The American Cancer Society estimates there will be nearly 2.0 million new cancer cases and over 600,000 cancer-related deaths in 2024. [2] Lung cancer remains  the second most common cancer in both men and women,, accounting for approximately 12%–13% of new cancer cases [1,2] Importantly, cancers of the lung and bronchus continue to represent the leading cause of cancer-related mortality, with an estimated 125,070 deaths in 2024, corresponding to about 21–22% of all cancer deaths in the United States [1–3]

Cancer screening has contributed to improved outcomes in many common cancers. For example, earlier detection with mammography and advances in therapy resulted in a 41% reduction in breast cancer mortality between 1989-2018 [5]. Similarly,  colon cancer mortality decreased 55% between 1970 and 2018, largely attributed to early detection through stool testing, colonoscopy or CT colonography, combined with improved treatments. More recently, randomized controlled trials such as the NLST and NELSON have demonstrated that lung cancer screening with low-dose CT (LDCT) reduces lung cancer mortality by approximately 16–21% in high-risk individuals, leading to guideline recommendations for annual LDCT screening in these populations [4-6].

As with any screening test, the goal is for the benefit of early detection and improved outcomes to outweigh the risks. Potential harms include false positives or false negatives, patient anxiety, and medical costs related to the screening exam and subsequent testing prompted by  incidental findings. Overdiagnosis is also a concern, with estimates of around 18% for LDCT screening [4]. In addition, radiation dose must be considered, as repeated annual scans carry a small risk of radiation-induced malignancy. To ensure appropriate use, current guidelines emphasize shared decision-making to weigh benefits and risks for each patient [6].

For most of the 20th century, the age-adjusted cancer death rate increased and peaked in 1991. Since then, rates have declined by about 31%, driven primarily by progress against the four most common cancer types, breast, prostate, colorectal and lung cancers and attributed to reduced smoking, earlier cancer detection and improved treatments. The incidence and mortality trends of lung cancer are declining, largely due to reduction in smoking, yet the overall relative survival remains low at 21% at 5 years. [1] Unlike breast, colorectal, and prostate cancer, where effective screening tests have been established for decades, a proven screening tool for lung cancer was only realized in recent years. Earlier methods such as chest radiography and sputum cytology, studied since the 1950s, showed no mortality benefit. 

The National Lung Screening Trial (NLST), published in 2011, enrolled individuals aged 55–74 years with at least a 30 pack-year smoking history, including former smokers within 15 years of quitting, and demonstrated that low-dose CT (LDCT) using ~1.5 mSv per scan (about 20% of the radiation dose of a standard chest CT at that time) reduced lung cancer mortality by 20%. The Dutch-Belgian NELSON trial, which included predominantly men aged 50–74 years, similarly showed that LDCT screening in high-risk individuals led to a significant reduction in lung cancer mortality. Together, these trials established that LDCT reduces lung cancer mortality by approximately 19–21%, corresponding to 3–4 fewer lung cancer deaths per 1,000 individuals screened [4,5]. These findings have led to national and international guideline recommendations for annual LDCT screening in high-risk populations [2,5]. 

In 2013, the United States Preventive Services Task Force (USPSTF) first recommended annual lung cancer screening with low-dose CT for persons age 55 through 80 years with a 30-pack year history of smoking who currently smoke or have quit within the last 15 years, citing smoking and older age as the two most important risk factors for lung cancer. This recommendation was updated in March 2021 after the USPSTF reviewed new systematic evidence and commissioned collaborative modeling studies to evaluate accuracy, benefits, harms, and optimal screening strategies [8,9]. The 2021 Final Recommendation of USPTF expanded eligibility from the 2013 recommendation in both age and smoking history. The new recommendation is LDCT screening for lung cancer in adults age 50-80 years with a 20-pack year history and currently smoke or quit smoking within 15 years. [3] This expansion was shown to increase the number of eligible individuals by nearly 90%, improve mortality reduction, and reduce disparities in screening access, particularly among women and racial/ethnic minorities [7,9]. The recommendation to discontinue screening after 15 years of smoking cessation or in patients with health problems limiting life expectancy or willingness to undergo curative surgery remains unchanged from the 2013 guideline [3].

As imaging experts, radiologists are uniquelyposition to educate and inform referring providers and patients about the benefits of low-dose CT (LDCT) screening to reduce lung cancer mortality while adhering to the principles of ALARA and maintain the pledge to Image Wisely [10,13]. Radiologists play a central role in ensuring evidence-based practice by applying validated protocols, minimizing radiation exposure, and communicating both the benefits and potential risks of screening [10]. 

There are numerous resources available to support radiologists, providers, and patients In this effort, including  patient-centered information on RadiologyInfo.org and clinical resources, and professional resources through the American College of Radiology (ACR), such as the requirements for ACR Lung Cancer Screening designation. Collaboration with referring providers is essential, as radiologists act as consultants and educators in an era where direct contact can be limited by PACS workflows [11,12].

Despite proven mortality benefits, lung cancer screening remains underutilized, with fewer than 20% of eligible individuals under prior USPSTF criteria undergoing LDCT. Increasing awareness and engagement, particularly for the newly eligible population under the expanded 2021 recommendations, represents a major opportunity. By championing the life-saving benefits of LDCT and ensuring its safe, effective application, radiologists can add significant value to patient care [13].

References

1. Bandi P, Star J, Ashad-Bishop K, et al. Lung Cancer Screening in the US, 2022. JAMA Intern Med. 2024;184(8):882-891. doi:10.1001/jamainternmed.2024.1655 
2. Wolf AMD, Oeffinger KC, Shih TY, et al. Screening for Lung Cancer: 2023 Guideline Update From the American Cancer Society. CA Cancer J Clin. 2024;74(1):50-81. doi:10.3322/caac.21811
3. Krist AH, Davidson KW, Mangione CM, et al. Screening for Lung Cancer: US Preventive Services Task Force Recommendation Statement. JAMA. 2021;325(10):962-970. doi:10.1001/jama.2021.1117 
4. Bonney A, Malouf R, Marchal C, et al. Impact of Low-Dose Computed Tomography (LDCT) Screening on Lung Cancer-Related Mortality. Cochrane Database Syst Rev. 2022;8:CD013829. doi:10.1002/14651858.CD013829.pub2. 
5. Adams SJ, Stone E, Baldwin DR, et al. Lung Cancer Screening. Lancet. 2023;401(10374):390-408. doi:10.1016/S0140-6736(22)01694-4.
6. Mazzone PJ, Silvestri GA, Souter LH, et al. Screening for Lung Cancer: CHEST Guideline and Expert Panel Report. Chest. 2021;160(5):e427-e494. doi:10.1016/j.chest.2021.06.063. 
7. Meza R, Jeon J, Toumazis I, et al. Evaluation of the Benefits and Harms of Lung Cancer Screening With Low-Dose Computed Tomography: Modeling Study for the US Preventive Services Task Force. JAMA.2021;325(10):988–997.
8. Jonas DE, Reuland DS, Reddy SM, et al. Screening for Lung Cancer With Low-Dose Computed Tomography: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force. JAMA. 2021;325(10):971-987. doi:10.1001/jama.2021.0377.
9. Ritzwoller DP, Meza R, Carroll NM, et al. Evaluation of Population-Level Changes Associated With the 2021 US Preventive Services Task Force Lung Cancer Screening Recommendations in Community-Based Health Care Systems. JAMA Netw Open. 2021;4(10):e2128176. doi:10.1001/jamanetworkopen.2021.28176.
10. Lavelle LP, Dunne RM, Carroll AG, Malone DE. Evidence-Based Practice of Radiology. Radiographics. 2015;35(6):1802-1813. doi:10.1148/rg.2015150027.
11. Berlin L. Contemporary Risk Management for Radiologists. Radiographics. 2018;38(6):1717-1728. doi:10.1148/rg.2018180012.
12. Bettmann MA, Oikarinen H, Rehani M, et al. Clinical Imaging Guidelines Part 4: Challenges in Identifying, Engaging and Collaborating With Stakeholders. J Am Coll Radiol. 2015;12(4):370-375. doi:10.1016/j.jacr.2014.07.020.
13. Damilakis J, Granata C, Kotter E, Brkljacic B. Balancing Patients’ Benefits and Risks in Computed Tomography: A European Society of Radiology “EuroSafe Imaging” Viewpoint. Eur Radiol. 2025. doi:10.1007/s00330-025-11911-8.