Dr. Nathan Pennell and Dr. Cheryl Czerlanis discuss challenges in lung cancer screening and potential solutions to increase screening rates, including the use of AI to enhance risk prediction and screening processes.

Transcript

Dr. Nate Pennell: Hello, and welcome to By the Book, a monthly podcast series for ASCO Education that features engaging discussions between editors and authors from the ASCO Educational Book. I'm Dr. Nate Pennell, the co-director of the Cleveland Clinic Lung Cancer Program and vice chair of clinical research for the Taussig Cancer Center. I'm also the editor-in-chief for the ASCO Educational Book. 

Lung cancer is one of the leading causes of cancer-related mortality worldwide, and most cases are diagnosed at advanced stages where curative treatment options are limited. On the opposite end, early-stage lung cancers are very curable. If only we could find more patients at that early stage, an approach that has revolutionized survival for other cancer types such as colorectal and breast cancer. 

On today's episode, I'm delighted to be joined by Dr. Cheryl Czerlanis, a professor of medicine and thoracic medical oncologist at the University of Wisconsin Carbone Cancer Center, to discuss her article titled, "Broadening the Net: Overcoming Challenges and Embracing Novel Technologies in Lung Cancer Screening." The article was recently published in the ASCO Educational Book and featured in an Education Session at the 2025 ASCO Annual Meeting. Our full disclosures are available in the transcript of this episode. 

Cheryl, it's great to have you on the podcast today. Thanks for being here.

Dr. Cheryl Czerlanis: Thanks, Nate. It’s great to be here with you.

Dr. Nate Pennell: So, I'd like to just start by asking you a little bit about the importance of lung cancer screening and what evidence is there that lung cancer screening is beneficial.

Dr. Cheryl Czerlanis: Thank you. Lung cancer screening is extremely important because we know that lung cancer survival is closely tied to stage at diagnosis. We have made significant progress in the treatment of lung cancer, especially over the past decade, with the introduction of immunotherapies and targeted therapies based on personalized evaluation of genomic alterations. But the reality is that outside of a lung screening program, most patients with lung cancer present with symptoms related to advanced cancer, where our ability to cure the disease is more limited. 

While lung cancer screening has been studied for years, the National Lung Screening Trial, or the NLST, first reported in 2011 a significant reduction in lung cancer deaths through screening. Annual low-dose CT scans were performed in a high-risk population for lung cancer in comparison to chest X-ray. The study population was comprised of asymptomatic persons aged 55 to 74 with a 30-pack-year history of smoking who were either active smokers or had quit within 15 years. The low-dose CT screening was associated with a 20% relative risk reduction in lung cancer-related mortality. A similar magnitude of benefit was also reported in the NELSON trial, which was a large European randomized trial comparing low-dose CT with a control group receiving no screening.

Dr. Nate Pennell: So, this led, of course, to approval from CMS (Centers for Medicare and Medicaid Services) for lung cancer screening in the Medicare population, probably about 10 years ago now, I think. And there are now two major trials showing an unequivocal reduction in lung cancer-related mortality and even evidence that it reduces overall mortality with lung cancer screening. But despite this, lung cancer screening rates are very low in the United States. So, first of all, what's going on? Why are we not seeing the kinds of screening rates that we see with mammography and colonoscopy? And what are the barriers to that here?

Dr. Cheryl Czerlanis: That's a great question. Thank you, Nate. In the United States, recruitment for lung cancer screening programs has faced numerous challenges, including those related to socioeconomic, cultural, logistical, and even racial disparities. Our current lung cancer screening guidelines are somewhat imprecise and often fail to address differences that we know exist in sex, smoking history, socioeconomic status, and ethnicity. We also see underrepresentation in certain groups, including African Americans and other minorities, and special populations, including individuals with HIV. And even where lung cancer screening is readily available and we have evidence of its efficacy, uptake can be low due to both provider and patient factors. On the provider side, barriers include having insufficient time in a clinic visit for shared decision-making, fear of missed test results, lack of awareness about current guidelines, concerns about cost, potential harms, and evaluating both true and false-positive test results. 

And then on the patient side, barriers include concerns about cost, fear of getting a cancer diagnosis, stigma associated with tobacco smoking, and misconceptions about the treatability of lung cancer.

Dr. Nate Pennell: I think those last two are really what make lung cancer unique compared to, say, for example, breast cancer, where there really is a public acceptance of the value of mammography and that breast cancer is no one's fault and that it really is embraced as an active way you can take care of yourself by getting your breast cancer screening. Whereas in lung cancer, between the stigma of smoking and the concern that, you know, it's a death sentence, I think we really have some work to be made up, which we'll talk about in a minute about what we can do to help improve this. 

Now, that's in the U.S. I think things are probably, I would imagine, even worse when we leave the U.S. and look outside, especially at low- and middle-income countries.

Dr. Cheryl Czerlanis: Yes, globally, this issue is even more complex than it is in the United States. Widespread implementation of low-dose CT imaging for lung cancer screening is limited by manpower, infrastructure, and economic constraints. Many low- and middle-income countries even lack sufficient CT machines, trained personnel, and specialized facilities for accurate and timely screenings. Even in urban centers with advanced diagnostic facilities, the high screening and follow-up care costs can limit access. Rural populations face additional barriers, such as geographic inaccessibility of urban centers, transportation costs, language barriers, and mistrust of healthcare systems. In addition, healthcare systems in these regions often prioritize infectious diseases and maternal health, leaving limited room for investments in noncommunicable disease prevention like lung cancer screening. Policymakers often struggle to justify allocating resources to lung cancer screening when immediate healthcare needs remain unmet. Urban-rural disparities exacerbate these challenges, with rural regions frequently lacking the infrastructure and resources to sustain screening programs.

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