For Lung Cancer Screening, Geographic Location Matters

November 14, 2020
Whitney J. Palmer

States with higher lung cancer burden have lower low-dose CT lung cancer screening rates.

When it comes to lung cancer screening rates, not all states are equal. In fact, according to a new study, in states where the lung cancer burden is higher, an anticipated more-robust level of lung cancer screening does not exist with only one notable exception – Kentucky.

In the first population-based, state-level study of lung cancer screening rates, researchers from the American Cancer Society (ACS) and the National Lung Cancer Roundtable, determined that screening rates swing wildly based upon several factors, including geographic location. They published their results on Nov. 12 in JNCI: The Journal of the National Cancer Institute.

Their findings come on the heels of recent data that shows low-dose CT (LDCT) lung cancer screening does, in fact, significantly reduce lung cancer-related morality even though existing data from the Centers for Disease Control & Prevention shows lung cancer screening of any kind is still lagging at less than 4.5 percent of eligible adults.

“The increasing, but low, utilization of lung cancer screening reflects both ongoing efforts to screening eligible adults, and the many challenges to do so,” said Stacey Fedewa, Ph.D., MPH, ACS senior principle scientist and lead for this investigation.

Related Content: CT Lung Cancer Screening Underperforms with Participation and Detection

With roughly 135,720 lung cancer deaths anticipated this year in this United States, Fedewa’s team looked at what could be behind the low – and differing – lung cancer screening rates in all 50 states, as well as Washington, D.C. In particular, they looked at how rates changed from 2016 to 2018 and how those rates correlated with state lung cancer burden, patient sociodemographic status, and access to lung cancer screening services.

By pulling data on screening events from adults aged 55-to-80 included in the American College of Radiology’s Lung Cancer Screening Registry, the team found that only one in 20 eligible adults actually get screening for lung cancer across the country. Specifically, they examined 268,109 scans from 2016, 278,632 from 2017, and 406,498 in 2018 with screening rates of 3.3 percent, 3.4 percent, and 5.0 percent, respectively.

While LDCT screening rates are trending upward, the team said, they are still low with a national average of 5 percent-to-6 percent of eligible adults undergoing screening. And, most alarmingly, the team said, state-by-state screening rates can be vastly different, showing patients in the states struggling most with lung cancer are not necessarily getting the screening they need. Kentucky, with its high lung cancer incidence, they said, is the one outlier.

Related Content: Focus on Smokers, Patients With Negative Lung CTs to Improve Lung Cancer Screening Adherence

“Kentucky, which has supported screening implementation efforts, is unique as it screening rates are over twice the national average and four times that of other high lung cancer burden states like West Virginia and Arkansas,” Fedewa said.

In particular, the team noted, Kentucky expanded Medicaid and does not require pre-authorization for the screening scan, making it much easier for providers to order the imaging. Their state government also publicly supported stronger screening efforts, and grassroots community organizations got behind efforts to expand screening access. As a result, even though the state holds both the nation’s highest lung cancer mortality rate, it also holds the highest screening rate – 13.7 percent.

The picture for the rest of the country is different, however, the team said. From the data the team reviewed, they found that several Northeastern states, including Massachusetts, Vermont, and New Hampshire, have a low lung cancer burden of fewer than 44 lung cancer deaths per 100,000 individuals. But, their screening rates are the highest, hovering between 12.8 percent and 15.2 percent. The situation was flipped for Southern states. Mississippi, West Virginia, and Arkansas have more than 50 lung cancer deaths per 100,000 people, and their screening rates fell below 4 percent of eligible adults.

Overall, their analysis showed screening rates were approximately 20 percent lower in states with higher proportions of uninsured adults who were smokers, and rates were even lower – 40 percent less – in states that had only a few screening facilities. These differences point to critical gaps in screening access, they said.

“Even with Medicaid coverage, reimbursement can be low, disincentivizing providers from offering screening to this vulnerable, yet commonly eligible community,” the team said. “Without addressing critical gaps in health insurance and adequate reimbursement for [lung cancer screening], its use will likely remain stunted.”

Screening rate differences also broke down along socioeconomic lines. Women who smoked were more likely to get screened, but smokers who were Hispanic were less likely. In fact, the data assessments revealed that states with adult, Hispanic smokers had screening rates that fell significantly below the national average. It is possible, the investigator said, that several barriers to screening could exist in these instances. For example, knowledge avoidance, stigma, false positive worry, and logistical barriers, such as no time off work for a doctor’s appointment, could be playing into whether an eligible adult receives screening.

Even with a robust population, this study did have limitations, the authors said. Clinics do not always have sufficient smoking histories on patients, and individuals who smoke are known to have less contact with primary care providers. And, in some instances, providers, themselves, can limit access because they are focused on other aspects of the patient's health or they want to avoid the pre-authorization requirements that can exist.

Despite those limitations and the existing stumbling blocks, though, the team said, more work needs to be done to increase screening.

“Deliberate efforts from various stakeholders, such as policy makers, cancer control, health systems, and providers are needed to boost lung cancer screening rates among eligible adults with a heavy smoking history, a group facing multiples barriers to lung cancer screening and cancer care,” they said. “If states know what their lung cancer screening rates are, they can set a goal and track progress toward it.”

For more coverage based on industry expert insights and research, subscribe to the Diagnostic Imaging e-Newsletter here.

Related Content:

CT | Oncology CT | News