The Shifting Sands of Lung Cancer Screening The Shifting Sands of Lung Cancer Screening

An analysis of trends in lung cancer screening since March 2021 when the U.S. Preventive Services Task Force (USPSTF) expanded the eligibility criteria for lung cancer screening, shows that significantly more Black men have been screened for lung cancer, but not women or undereducated people.

The eligibility for lung cancer screening was expanded in 2021 to include men and women under 50 years old and people who smoke at least one pack of cigarettes a day for the last 20 years. “

“Expansion of screening criteria is a critical first step to achieving equity in lung cancer screening for all high-risk populations, but myriad challenges remain before individuals enter the door for screening,” wrote the authors, led by Julie A. Barta, MD, Thomas Jefferson University, Philadelphia. “Health policy changes must occur simultaneously with efforts to expand community outreach, overcome logistical barriers, and facilitate screening adherence. Only after comprehensive strategies to dismantle screening barriers are identified, validated, and implemented can there be a truly equitable landscape for lung cancer screening.”

For the study, published in JAMA Open Network, researchers examined rates of centralized lung cancer screening in the Baltimore area. In addition to expanding lung cancer screening generally, there was hope that the expanded criteria might increase uptake of screening in populations that are traditionally underserved, such as African American, Hispanic, and female patients. Of 815 people screened during the study period (March-December 2021), 161 were newly eligible for screening under the 2021 criteria.

“There’s been quite a bit of work in the field demonstrating that Black men and women develop lung cancer at more advanced stages of disease, and they often are diagnosed at younger ages and have fewer pack-years of smoking. So the hypothesis was that this would reduce some of the disparities seen in lung cancer screening by making more people eligible,” Barta said in an interview.

The researchers categorized participants as those who would have been eligible for screening under the USPSTF 2013 guideline (age 55 or older, 30 or more pack-years, quit within the past 15 years), and those who would be eligible under the 2021 guideline (age 50 or older, 20 or more pack-years, quit within the past 15 years). Of the 2021 cohort, 54.5% were African American, versus 39.5% of the 2013 cohort (= .002). There were no differences between the cohorts with respect to education level or gender.

“Although we’ve seen some encouraging improvement in terms of getting more eligible patients into our screening program, there’s still a lot of work to be done in the field,” Barta said. “Diagnosing lung cancer at earlier stages of disease is more cost effective in general for the health care system than fighting lung cancer at advanced stages, which requires more complex and multimodal and prolonged therapies.”

New Evidence: Chest CTs for Lung Cancer Screening Reduces Incidence of Advanced Lung Cancer

In an analysis of the SEER database presented in June at the annual meeting of the American Society of Clinical Oncology, the adoption of low-dose chest computed tomography (LDCT) led to fewer diagnoses of advanced lung cancer, although these declines varied significantly by race and ethnicity. Non-Hispanic Blacks seemed to benefit the most with a 55% decline (< .01), while Hispanics had the lowest rate of decline at 41% (< .01). The change was recommended by USPSTF in 2013 after the National Lung Screening Trial revealed a 20% relative reduction in mortality when CT scans were used instead of chest radiography. The Centers for Medicare and Medicaid Services approved coverage of the screen in 2015.

The SEER study looked at data from 400,343 individuals from 2004-2014 (preintervention) and 2015-2018 (postintervention). The age-adjusted incidence of advanced lung cancer declined during both periods, but the decline was sharper between 2015 and 2018, with three fewer cases per 100,000 people than 2004-2014 (< .01). Similar patterns were seen in subanalyses of males and females, non-Hispanic Whites, non-Hispanic Blacks, and Hispanics. The relative declines were largest in women, non-Hispanic Blacks, and people who lived outside of Metropolitan areas.

During a Q&A session that followed the presentation, Robert Smith, PhD, pointed out that the bar for eligibility of lung cancer risk has been set quite high, following the eligibility criteria for clinical trials. He noted that many patients who could be eligible for screening are still missed because of a lack of clinical routines designed to identify eligible patients. “We are missing opportunities to prevent avertable lung cancer deaths,” said Smith, senior vice president of cancer screening at the American Cancer Society.

On the other hand, screening-prompted biopsies have the potential to cause harm, particularly in patients who already have lung disease, said Douglas Allen Arenberg, MD, professor at the University of Michigan, Ann Arbor. “I think that’s what scares most people is the potential downside, which is very hard to measure outside of a clinical trial,” said Arenberg, who served as a discussant for the presentation.

One way to reduce that risk is to identify biomarkers, either for screens or for incidentally-detected nodules, that have good negative predictive value. “If I had a blood test that is as good as a negative PET scan, I’m going to be much more likely to say, ‘Yeah, you’re 40 and your grandfather had lung cancer. Maybe you should get a CT. If we had that, we could screen a lot more people. Right now, I would discourage anybody who is at low risk from getting screened because when they come to me, the biggest opportunity I have to do harm is when I do a biopsy, and you always remember the ones that go wrong,” he said.

Arenberg also called for improvements in electronic medical records to better flag at-risk patients. “I think we as physicians have to demand more of the software developers that create these EMRs for us,” he said.

Another study in the same session used data from 1,391,088 patients drawn from the National Cancer Database between 2010 and 2017 to examine trends in diagnosis of stage I cancer. In 2010, 23.5% of patients were diagnosed as stage I, versus 29.1% in 2017. Stage I incidence increased from 25.8% to 31.7% in non-small cell lung cancer, but there was no statistically significant change in small cell lung cancer. As with the SEER database study, the researchers noted that the shift toward stage I diagnoses predated the recommendation of LDCT.

Arenberg suggested that the trend may come down to increased frequency of CT scans, which often collect incidental images of the lungs. He added that better access to care may also be helping to drive the change. “How much of that might have had something to do with the introduction 5 or 10 years earlier of the Affordable Care Act and people just simply having access to care and taking advantage of that?” Arenberg said.

But Arenberg said that not even screening can explain all the data. He referenced a stage shift in patients of all age groups in the National Cancer Database study, even those too young to be eligible for screening. “There’s something else going on here. It would be nice for us to understand what caused these trends, so perhaps we could accentuate that trend even more, but stage shifts are clearly occurring in lung cancer,” Arenberg said.

Barta has received grants from Genentech Health Equity Innovations Fund. Arenberg has no relevant financial disclosures. Smith’s potential disclosures could not be ascertained.

This article originally appeared on MDedge.com, part of the Medscape Professional Network.