Add Race to Lung Cancer Screening Criteria, Study Suggests

Add Race to Lung Cancer Screening Criteria, Study Suggests

Nick Mulcahy

August 02, 2018

Adding race to the criteria for lung cancer screening with low-dose CT (LDCT) in the United States might bolster efficacy, suggest researchers in a research letter published online August 2 in JAMA Oncology.

The team found that lung cancer screening in an urban, largely black cohort yielded roughly double the rates of positive screens and detected lung cancers compared with results from the largely white National Lung Screening Trial (NLST).

The new research is “one of the first studies specifically focusing on screening in a predominantly minority population,” said lead author Mary Pasquinelli, MS, APRN, from the University of Illinois at Chicago (UIC), in an email to Medscape Medical News.

She and her colleagues point out that, currently, the only recommended screening criteria in the United States are age (55 to 80 years) and smoking history (30 pack-years and currently smoking or having quit within the last 15 years).

The recommendation to screen comes from results of the NLST, which showed a 20% reduction in disease-specific mortality with LDCT compared with chest radiography.

Importantly, 91% of the landmark study’s participants were white and only 4.5% were black. This looks like a shortcoming because black Americans have the highest lung cancer mortality in the United States, the researchers point out.

The team wondered how screening would perform in a cohort with a larger percentage of blacks, and they speculated that the mortality disparity could be improved if race were emphasized in screening recommendations.

So, they retrospectively analyzed an urban cohort — individuals who underwent lung cancer screening at their center, UIC, which mainly serves minority populations in the Midwest’s biggest city.

Specifically, they looked at the 500 baseline LDCT screens at UIC (from 2015 to 2017) and compared them to the 26,722 baseline screens from the NLST’s LDCT arm.

The UIC cohort had much higher percentages of blacks (69.6%) and Hispanics/Latinos (10.6%) than the NLST’s arm (4.5% and 1.8%, respectively).

Notably, 24.6% of the UIC cohort had positive LDCT screens (Lung-RADS class 3 or 4) vs only 13.7% in the NLST arm (P < .001).

Furthermore, 2.6% of the UIC cohort had lung cancer detected vs 1.1% of the NLST arm (P = .002).

The UIC cohort also had a higher percentage of current smokers than the NLST arm (72.8% vs 48.1%).

These are “real world differences,” say the study authors.

The findings also jibe with a secondary analysis from NLST showing that reduction in lung cancer mortality was greatest among African American participants (Am J Respir Crit Care Med. 2015;192:200-208).

The new data support the argument that the screening recommendations need tweaking.

“This report provides experiential evidence that is consistent with the notion that a more-detailed assessment of individual risk of lung cancer may be more effective than focusing only on age and smoking status criteria,” write the  authors.

“Our study supports the use of a risk assessment model (such as the Tammemagi lung cancer risk calculator) that takes into account such factors as race/ethnicity and COPD [chronic obstructive pulmonary disease]/emphysema among other factors,” Pasquinelli added.

The idea is timely, the authors say, because “the magnitude of the disparity in lung cancer mortality between African American and white individuals has been widening.”

The authors have disclosed no relevant financial relationships.

JAMA Oncol. Published online August 2, 2018. Abstract

Follow Medscape senior journalist Nick Mulcahy on Twitter: @MulcahyNick

For more from Medscape Oncology, follow us on Twitter: @MedscapeOnc