German mesothelioma researchers recently published a study further proving the causal relationship between asbestos exposure and mesothelioma. The study was published in the International Journal of Hygiene and Environmental Health.
According to the authors of the study, “The objective of this analysis was the estimation of the cancer risks of asbestos and asbestosis in a surveillance cohort of high-exposed German workers.” A cohort is defined as a group of people who share a condition or certain experience within a defined period of time. The cohort in this study consisted of 576 German men who had been occupationally exposed to asbestos.
All 576 asbestos workers underwent a high-resolution computer tomography (CT scan) of the chest between 1993 and 1997. A mortality follow-up was performed until 2007 to collect data on the participants and assess their development of conditions such as asbestosis and malignant mesothelioma.
The authors note that “Germany is among the few countries that conduct mandatory preventive occupational health examinations in asbestos-exposed workers. The Central Registration Agency for Employees Exposed to asbestos Dust was founded in 1972 to organize a surveillance program.” The researchers selected eligible participants for the cohort from this asbestos registration agency, excluding persons over 70 years old and those know to reject medical investigations.
The median age of the participants was 63 and all were considered highly exposed to asbestos. Approximately 50 percent of participants were exposed to asbestos for 25 or more years. The duration of exposure lasted an average of 20 years among the cohort participants.
Imaging scans revealed 363 (63%) participants with pleural thickenings or pleural plaques. A total of 178 (31%) exhibited fibrotic lung alterations. Scans proved that 53% of participants had certifiable occupational asbestos disease.
The mortality follow-up conducted until 2007 revealed 128 participants had passed away; of these participants, the cause of death was retrieved for 113. A total of 58 died from cancer, 15 from pleural mesothelioma, eight from lung cancer, 17 from cancer of the digestive system, and four from lymphatic cancer.
Overall, a high risk was observed for pleural mesothelioma, which decreased after cessation of exposure. Asbestosis was found to be a significant risk factor for later development of mesothelioma. In conclusion, the researchers found that “Fibrotic alteration of the pleura and lung were confirmed as predictors of pleural mesothelioma as well as lung cancer and underpin the necessity to elucidate the underlying biological process of fibrosis in relation to cancer development.”
Additional information on mesothelioma and asbestos exposure may be found through the mesothelioma Center.