When the American Cancer Society recently unveiled changes to its lung cancer screening guidance, the aim was to remove barriers to screening and catch more cancers in high-risk people earlier.
Although the lung cancer death rate has declined significantly over the past few decades, lung cancer remains the leading cause of cancer deaths worldwide.
Detecting lung cancer early is key to improving survival. Still, lung cancer screening rates are poor. In 2021, the American Lung Association estimated that 14 million US adults qualified for lung cancer screening, but only 5.8% received it.
Smokers or former smokers without symptoms may forgo regular screening and only receive their screening scan after symptoms emerge, explained Janani S. Reisenauer, MD, Division Chair of Thoracic Surgery at Mayo Clinic, Rochester, Minnesota. But by the time symptoms develop, the cancer is typically more advanced, and treatment options become more limited.
The goal of the new American Cancer Society guidelines, published in early November 2023, is to identify lung cancers at earlier stages when they are easier to treat.
The new guidelines, which update a 2013 version, expand the eligibility age for screening and the pool of current and former smokers who qualify for annual screening with low-dose CT. Almost 5 million more high-risk people will now qualify for regular lung cancer screening, the guideline authors estimated.
But will expanding screening help reduce deaths from lung cancer? And perhaps just as important, will the guidelines move the needle on the “disappointingly low” lung cancer screening rates up to this point?
“I definitely think it’s a step in the right direction,” said Lecia V. Sequist, MD, MPH, clinical researcher and lung cancer medical oncologist, Massachusetts General Hospital Cancer Center, Boston, Massachusetts.
The new guidelines lowered the age for annual lung cancer screening among asymptomatic former or current smokers from 55-74 years to 50-80 years. The update also now considers a high-risk person anyone with a 20-pack-year history, down from a 30-pack-year history, and removes the requirement that former smokers must have quit within 15 years to be eligible for screening.
As people age, their risk for lung cancer increases, so it makes sense to screen all former smokers regardless of when they quit, explained Kim Lori Sandler, MD, from Vanderbilt University Medical Center, Nashville, Tennessee, and cochair of the American College of Radiology’s Lung Cancer Screening Steering Committee.
“There’s really nothing magical or drastic that happens at the 15-year mark,” Sequist agreed. For “someone who quit 14 years ago versus 16 years ago, it is essentially the same risk, and so scientifically it doesn’t really make sense to impose an artificial cut-off where no change in risk exists.”
The latest evidence reviewed in the new guidelines shows that expanding the guidelines would identify more early-stage cancers and potentially save lives. The authors modeled the benefits and harms of lung cancer screening using several scenarios.
Moving the start age from 55 to 50 years would lead to a 15% reduction in lung cancer mortality in men aged 50-54 years, the model suggested.
Removing the 15-year timeline for quitting smoking also would also improve outcomes. Compared with scenarios that included the 15-year quit timeline for former smokers, those that removed the limit would result in a 37.3% increase in screening exams, a 21% increase in would avert lung cancer deaths, and offer a 19% increase in life-years gained per 100,000 population.
Overall, the evidence indicates that, “if fully implemented, these recommendations have a high likelihood of significantly reducing death and suffering from lung cancer in the United States,” the guideline authors wrote.
But screening more people also comes with risks, such as more false-positive findings, which could lead to extra scans, invasive tests for tissue sampling, or even procedures for benign disease, Sandler explained. The latter “is what we really need to avoid.”
Even so, Sandler believes the current guidelines show that the benefit of screening “is great enough that it’s worth including these additional individuals.”
Guidelines Are Not Enough
But will expanding the screening criteria prompt more eligible individuals to receive their CT scans?
Simply expanding the eligibility criteria, by itself, likely won’t measurably improve screening uptake, said Paolo Boffetta, MD, MPH, of Stony Brook Cancer Center, Stony Brook, New York.
Healthcare and insurance access along with patient demand may present the most significant barriers to improving screening uptake.
The “issue is not the guideline as much as it’s the healthcare system,” said Otis W. Brawley, MD, professor of oncology at the Johns Hopkins University School of Medicine, Baltimore, Maryland.
Access to screening at hospitals with limited CT scanners and staff could present one major issue.
When Brawley worked at a large inner-city safety net hospital in Atlanta, patients with lung cancer frequently had to wait over a week to use one of the four CT scanners, he recalled. Adding to these delays, we didn’t have enough people to read the screens or enough people to do the diagnostics for those who had abnormalities, said Brawley.
To increase lung cancer screening in this context would increase the wait time for patients who do have cancer, he said.
Insurance coverage could present a roadblock for some as well. While the 2021 US Preventive Services Task Force (USPSTF) recommendations largely align with the new ones from the American Cancer Society, there’s one key difference: The USPSTF still requires former smokers to have quit within 15 years to be eligible for annual screening.
Because the USPSTF recommendations dictate insurance coverage, some former smokers — those who quit more than 15 years ago — may not qualify for coverage and would have to pay out-of-pocket for screening.
Sequist, however, had a more optimistic outlook about screening uptake.
The American Cancer Society guidelines should remove some of the stigma surrounding lung cancer screening. Most people, when asked a lot of questions about their tobacco use and history, tend to downplay it because there’s shame associated with smoking, Sequist said. The new guidelines limit the information needed to determine eligibility.
Sequist also noted that the updated American Cancer Society guideline would improve screening rates because it simplifies the eligibility criteria and makes it easier for physicians to determine who qualifies.
The issue, however, is that some of these individuals — those who quit over 15 years ago — may not have their scan covered by insurance, which could preclude lower-income individuals from getting screened.
The American Cancer Society guidelines” do not necessarily translate into a change in policy,” which is “dictated by the USPSTF and payors such as Medicare,” explained Peter Mazzone, MD, MPH, director of the Lung Cancer Program and Lung Cancer Screening Program for the Respiratory Institute, Cleveland Clinic, Cleveland, Ohio.
On the patient side, Brawley noted, “we don’t yet have a large demand” for screening.
Many current and former smokers may put off lung cancer screening or not seek it out. Some may be unaware of their eligibility, while others may fear the outcome of a scan. Even among eligible individuals who do receive an initial scan, most — more than 75% — do not return for their next scan a year later, research showed.
Enhancing patient education and launching strong marketing campaigns would be a key element to encourage more people to get their annual screening and reduce the stigma associated with lung cancer as a smoker’s disease.
“Primary care physicians are integral in ensuring all eligible patients receive appropriate screening for lung cancer,” said Steven P. Furr, MD, president of the American Academy of Family Physicians and a family physician in Jackson, Alabama. “It is imperative that family physicians encourage screening in at-risk patients and counsel them on the importance of continued screening, as well as smoking cessation, if needed.”
Two authors of the new guidelines reported financial relationships with Seno Medical Instruments, the Genentech Foundation, Crispr Therapeutics, BEAM Therapeutics, Intellia Therapeutics, Editas Medicine, Freenome, and Guardant Health.
Rohit Malhotra is a medical expert and health journalist who offers evidence-based advice on fitness, nutrition, and mental well-being. His articles aim to help readers lead healthier lives.
