Lung cancer risk in past asbestos workers a few decades after exposure cessation and prospects for screening

Abstract

To ascertain whether the current risk of lung cancer in former asbestos workers was higher than in the general population, 1,557 past asbestos workers were recruited during statutory health examinations (from 2000 onward) and followed up for mortality. Standardized mortality ratios (SMRs) were calculated. Poisson regression was used to adjust the rate ratios (RRs) for confounders. SMR was about 1.00 in workers with or without pleural plaques and 4.62 (95% confidence interval: 0.61-18.1) in those with asbestosis. Adjusted RRs for lung cancer were 4.70 (0.99-22.5) for asbestosis, 4.35 (0.97-19.5) for former smokers, 6.82 (1.38-34.4) for current smokers. Currently, lung cancer mortality in past asbestos workers is similar to the general population, probably because workers more exposed /more susceptible could have died from lung cancer before the beginning of follow-up.

Pleural plaques in lung cancer screening by low-dose computed tomography: prevalence, association with lung cancer and mortality

“…Accordingly, several lung cancer risk models for selection of lung cancer screening population include asbestos exposure among risk factors, even in case of non-occupational exposure [ 3 , 7 ]. Non-occupational exposure is likely to become more relevant in industrialized countries were asbestos ban was issued more than 20 years ago [ 10 ]. The assessment of non-occupational exposure to asbestos is extremely challenging, indeed more controversial that the assessment of occupational exposure [ 25 ].…”

“…Among occupationally exposed subjects, the correlation between pleural plaques and lung cancer appears to be lower compared to the relative risk associated with asbestosis [ 10 ]. Both asbestosis and pleural plaques can be seen on LDCT, however pleural plaques are more specific than asbestosis findings in the absence of known exposure to asbestos.…”

“…Notably, parenchymal signs were not scored because they are not specific for asbestos exposure when the exposure is not formally confirmed. It would be ideal that reliable information about asbestos exposure in lung cancer screening allow specific investigation of interstitial lung abnormalities related with the exposure, since they are significantly related with the risk of lung cancer [ 10 ].…”

“…Pleural plaques are among the chest abnormalities significantly related with exposure to asbestos [ 8 , 9 ]. In the setting of professional exposure to asbestos, several studies reported the association between reduced survival and asbestos-related LDCT signs, including pleural plaques [ 4 , 10 ]. The detection of pleural plaques and their prognostic value in non-occupational setting has not been investigated, yet.…”

Low-dose CT for lung cancer screening: position paper from the Italian college of thoracic radiology

“…Smoking cessation decreases LC risk after 10 years since quitting [ 4 ]. Age is the second established risk factor for LC, and environmental and professional exposures represent additional risk factors [ 5 – 10 ].…”