Lung cancer risk prediction models and asbestos exposure: a validation study on the Western Australia Asbestos Review Program.

OBJECTIVES

Asbestos exposure raises the lung cancer risk and has supra-additive synergy alongside tobacco exposure. Lung cancer screening (LCS) is effective when high-risk populations are targeted. This study examined the utility of various LCS eligibility and risk prediction models in an asbestos-exposed population.

METHODS

The Western Australia Asbestos Review Program (ARP) consists of individuals with known exposure to asbestos. All participants underwent annual review with low-dose CT screening. The performance of the Prostate, Lung, Colorectal and Ovarian (PLCO)m2012, PLCOm2014 and PLCOocc models, Liverpool Lung Project V.2 (LLPv2) and Bach models, together with the United States Preventive Services Task Force (USPSTF)2021 and Australian LCS eligibility criteria were validated on the ARP.

RESULTS

The cohort consisted of 2126 participants of which 85.4% were male with a median (IQR) age of 70 (63-75) years old. Former smokers comprised 55.1% (n=1172) and never smokers 36.2% (n=769) of the cohort. Median smoking and cessation duration were 24 years (IQR: 13-72) and 32 years (IQR: 22-41), respectively. Lung cancer was diagnosed in 51 (2.4%) participants.When applying the risk models to the ARP cohort, the area under the curve for all models was modest, ranging from 0.602 to 0.675. All models underestimated risk in this cohort during calibration assessment, with the exception of the LLP V.2, which overestimated risk.

CONCLUSIONS

In an asbestos exposed population, current LCS eligibility criteria and risk models mostly underestimate the risk of lung cancer, reflecting the need for improved risk prediction models that adequately account for asbestos exposure.