Cornell research focuses attention on racial disparities in lung cancer screening

Ongoing work from researchers affiliated with the Cornell Center for Health Equity could help expand lung cancer screening eligibility for Black individuals, a particularly vulnerable population.

The research comes amid an ongoing debate about how expansive to make lung cancer screening with low-dose computed tomography (LDCT) and how best to balance testing benefits with harms. Leading national guidelines for screening often miss lung cancers among people with a range of backgrounds, including nonsmokers. They also don’t include potential risk factors such as family history and exposure to radon, pollution or secondhand smoke.

Critiques feature a racial perspective, too. While Black and white populations smoke at equivalent rates, previous investigations from the Cornell team and others show that Black individuals qualify for lung cancer screening less often. That disparity can harm health, as they face higher lung cancer incidence and mortality rates than members of other racial groups.

To address those consequences, the Cornell team has turned to a landmark dataset it previously tapped to compare screening eligibility for current and former smokers. This time, the group is connecting the data to Medicare claims for lung cancer treatment, to generate additional evidence for possible action.

“I think that tying it to the diagnosis of cancer — a very clinical outcome — strengthens the argument,” says Laura Pinheiro, an assistant professor of population health sciences at Weill Cornell Medicine. “Hopefully it lights a little bit of a fire under the people that make these types of decisions and establish guidelines.”

Pinheiro previously served as lead author for a paper the Cornell group published in 2021 in the journal JAMA Open Network — deliberately chosen for its unfettered public access. The paper focused on screening updates made earlier that year by an independent federal panel that drives coverage decisions by insurers.

The panel, the U.S. Preventive Services Task Force, made its changes in large part to expand eligibility for Black residents, following evidence of racial disparities in screening with its initial 2013 guidelines. A key study from 2019 showed that only a third of Black lung cancer patients would have been eligible for screening under 2013 guidelines, compared to half of white patients.

In response, the task force dropped the minimum age for annual screening from 55 to 50 and lowered the number of pack years from 30 to 20. It kept the caveat that people should be current smokers or have only quit within the past 15 years.

Following the change, Pinheiro and some of her colleagues at Weill Cornell Medicine identified a critical research question they felt positioned to answer: Would the update actually help reduce racial disparities in screening eligibility? That idea came to fruition thanks to the Cornell Center for Health Equity, where a number of the researchers are members.

“The center really enabled our collaboration and connected us together,” Pinheiro says.

Through that link, the team gained access to a unique and particularly valuable dataset, one that center co-director Dr. Monika Safford, a paper co-author, helped expand earlier in her academic career. It came from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) project, which has gathered a range of national information by following more than 30,000 non-Hispanic Black and white residents since 2003.

While those participants were drawn from across the country, they were concentrated in the Southeast — a region with particularly high smoking rates. The group also included a higher share of Black residents than the nation as whole, making up for the shortcomings of past health studies and ensuring a strong sample size.

“It’s a really incredibly rich data source for studying racial disparities,” Pinheiro says.

In their analysis, Pinheiro and her colleagues only considered REGARDS participants whose smoking histories were available, before removing nonsmokers and those too young or old for the screening guidelines. They ended up with about 14,000 participants, 40% of whom identified as Black.

The researchers found that the 2021 update increased screening eligibility for both racial groups and, on the surface, somewhat narrowed the gap between the two. Eligibility for Black participants rose from 19.2% to 28.8% and for white participants from 27.2% to 34.6% — reducing the racial gap from 8 percentage points to 5.8.

Still, the gap persisted. To explore the possible reasons, the researchers accounted for age and sex. They then adjusted for further differences among a range of socioeconomic factors previously shown to harm well-being. Among these social determinants of health: Education. Income. Social network size. Marital status. Insurance coverage. And home region, including how rural or racially segregated.

All of these factors appear to significantly affect the screening eligibility gap, the researchers found — particularly residential segregation. Further study is also needed: Adjusting for that specific list of social determinants showed the Cornell researchers that there are likely other factors that have yet to be conclusively identified.

“Perhaps lung cancer screening eligibility needs to be expanded to account a bit more for these social determinants of health,” Pinheiro says. “How can these factors be incorporated into the recommendations?”

Some outside research projects are exploring the idea of screening a wider range of adults, regardless of smoking history — though others argue that doing so could introduce harms.

Another idea, raised in the Cornell group’s 2021 paper, is to develop an individual risk model. Such an approach could potentially incorporate factors such as race and ethnicity, as well as social determinants of health.

The Weill Cornell team expects its Medicare claims research to shed further light on how these factors relate to lung cancer risk, even if they can’t demonstrate causation. Other members of the team, including senior and corresponding author of the 2021 paper, Dr. Erica Phillips, along with colleagues Drs. Lauren Groner and Rulla Tamimi, are using the study findings to tailor an ongoing intervention study. Led by Dr. Groner, the study aims to increase lung cancer screening rates among residents living in impoverished neighborhoods directed impacted by racial residential segregation.

“While our study may not alter the current USPTF guidelines, we can use it to impact how we approach lung cancer screening in our own health system,” said Dr. Phillips, who serves as the Associate Director of Community Outreach and Engagement for the Meyer Cancer Center at Weill Cornell and is a former co-director of community engagement for the Center for Health Equity.

Along with Dr. Tamimi, the two lead a newly funded center by the National Cancer Institute focused on cancer prevention in persistent poverty neighborhoods across New York City. The researchers are also seeking ways to look at lung cancer diagnoses in younger populations left out by the current guidelines.

While barriers to screening remain even with eligibility, the Cornell team feels its work could drive the conversation forward and ultimately make a difference.

“By just thinking about age and pack years, it’s not really taking into account some of these other nuances,” Pinheiro says. “It’s ignoring a group of individuals that could benefit a lot from additional screening.”