Fraser J H Brims1,2, Karen Kong2, Ed J A Harris1,2, Nita Sodhi-Berry3, Alison Reid4, Conor P Murray5, Peter J Franklin3, A Bill Musk3, Nicholas H de Klerk6. 1. Curtin Medical School and. 2. Department of Respiratory Medicine, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia. 3. School of Population and Global Health and. 4. School of Public Health, Curtin University, Perth, Western Australia, Australia. 5. Perth Children's Hospital, Perth, Western Australia, Australia. 6. Telethon Kids Institute, University of Western Australia, Perth, Western Australia, Australia; and.
Abstract
Rationale: Asbestos exposure is associated with a dose-dependent risk of lung cancer. The association between lung cancer and the presence of pleural plaques remains controversial. Objectives: To define the relationship between pleural plaques and lung cancer risk. Methods: Subjects were from two cohorts: 1) crocidolite mine and mill workers and Wittenoom Township residents and 2) a mixed-asbestos-fiber, mixed-occupation group. All subjects underwent annual review since 1990, chest X-ray or low-dose computed tomography scan, and outcome linkage to national cancer and mortality registry data. Cox regression, with adjustment for age (as the underlying matching time variable), was used to estimate hazard ratios (HRs) for lung cancer incidence by sex, tobacco smoking, asbestos exposure, presence of asbestosis, and pleural plaques. Measurements and Main Results: For all 4,240 subjects, mean age at follow up was 65.4 years, 3,486 (82.0%) were male, 1,315 (31.0%) had pleural plaques, and 1,353 (32.0%) had radiographic asbestosis. Overall, 3,042 (71.7%) were ever-smokers with mean tobacco exposure of 33 pack-years. In total, 200 lung cancers were recorded. Risk of lung cancer increased with cumulative exposure to cigarettes, asbestos, and presence of asbestosis. Pleural plaques did not confer any additional lung cancer risk in either cohort (cohort 1: HR, 1.03; 95% confidence interval, 0.64-1.67; P = 0.89; cohort 2: HR, 0.75; 95% confidence interval, 0.45-1.25; P = 0.28). Conclusions: The presence of pleural plaques on radiologic imaging does not confer additional increase in the risk of lung cancer. This result is consistent across two cohorts with differing asbestos fiber exposures and intensity.
Rationale: Asbestos exposure is associated with a dose-dependent risk of lung cancer. The association between lung cancer and the presence of pleural plaques remains controversial. Objectives: To define the relationship between pleural plaques and lung cancer risk. Methods: Subjects were from two cohorts: 1) crocidolite mine and mill workers and Wittenoom Township residents and 2) a mixed-asbestos-fiber, mixed-occupation group. All subjects underwent annual review since 1990, chest X-ray or low-dose computed tomography scan, and outcome linkage to national cancer and mortality registry data. Cox regression, with adjustment for age (as the underlying matching time variable), was used to estimate hazard ratios (HRs) for lung cancer incidence by sex, tobacco smoking, asbestos exposure, presence of asbestosis, and pleural plaques. Measurements and Main Results: For all 4,240 subjects, mean age at follow up was 65.4 years, 3,486 (82.0%) were male, 1,315 (31.0%) had pleural plaques, and 1,353 (32.0%) had radiographic asbestosis. Overall, 3,042 (71.7%) were ever-smokers with mean tobacco exposure of 33 pack-years. In total, 200 lung cancers were recorded. Risk of lung cancer increased with cumulative exposure to cigarettes, asbestos, and presence of asbestosis. Pleural plaques did not confer any additional lung cancer risk in either cohort (cohort 1: HR, 1.03; 95% confidence interval, 0.64-1.67; P = 0.89; cohort 2: HR, 0.75; 95% confidence interval, 0.45-1.25; P = 0.28). Conclusions: The presence of pleural plaques on radiologic imaging does not confer additional increase in the risk of lung cancer. This result is consistent across two cohorts with differing asbestos fiber exposures and intensity.
Authors: Eline Janssens; Zoë Mol; Lore Vandermeersch; Sabrina Lagniau; Karim Y Vermaelen; Jan P van Meerbeeck; Christophe Walgraeve; Elly Marcq; Kevin Lamote Journal: Front Oncol Date: 2022-05-06 Impact factor: 5.738