Newswise—A four-protein biomarker blood test improves lung cancer risk assessment over existing guidelines that rely solely upon smoking history, capturing risk for people who have ever smoked, not only for heavy smokers, an international research team reports in JAMA Oncology.

“This simple blood test demonstrates the potential of biomarker-based risk assessment to improve eligibility criteria for lung cancer screening with low-dose computed tomography,” said study co-senior author Sam Hanash, MD, PhD, professor of clinical cancer prevention at The University of Texas MD Anderson Cancer Center.

The biomarker panel achieved superior sensitivity—identification of smokers who later developed lung cancer—without increasing false-positives compared to guidelines for screening approved by the US Preventive Service Task Force (USPSTF) for heavy smokers based on age and smoking history.

USPSTF guidelines call for CT screening only of adults between ages 55 and 80 with a 30 pack-year smoking history who either smoke or have quit within the past 15 years.

“The biomarker panel more accurately identifies at-risk smokers who should proceed to screening, even if they’re not at the highest risk based on smoking history alone,” Hanash said. “A positive blood test means an ever-smoker is as much, if not more so, at risk of having lung cancer as a heavy smoker with a low biomarker score.”

The paper reports a validation study of the biomarker model in 63 ever-smoking patients who developed lung cancer within a year of initial blood sample collection compared to 90 matched controls in two large European population-based cohorts.

Researchers compared a model based on smoking history to an integrated model that included the biomarker score based on the four markers plus smoking history.

At the same level of false-positive rate (specificity) set by the USPSTF guidelines, the integrated test with biomarkers identified 63% of future lung cancer cases (40 of 63), compared to 42% (20 of 62) based on smoking history alone.

The improved detection rate, Hanash said, reflects the biomarker panel’s ability to identify at-risk people among the larger population of ever-smokers. In the validation study, smoking history did not improve prediction of future lung cancer cases beyond that provided by the biomarkers alone.

Hanash’s group worked with European researchers affiliated with the International Agency for Research on Cancer (IARC), part of the World Health Organization. Co-senior authors were Mattias Johansson, PhD, of IARC and Paul Brennan, PhD, head of the Section on Genetics at IARC.

MD Anderson’s Lung Cancer Moon Shot™, part of the institution’s Moon Shots Program™, provided initial support of Hanash’s research, mainly through funding from the Lyda Hill Foundation.