Risk factors

Working with asbestos is the major risk factor for mesothelioma.[15] In the United States, asbestos is the major cause of malignant mesothelioma. Indeed, the relationship between asbestos and mesothelioma is so strong that many consider mesothelioma a “signal” or “sentinel” tumor.[10][not in citation given][16][17][18][19] A history of asbestos exposure exists in most cases. However, mesothelioma has been reported in some individuals without any known exposure to asbestos. In rare cases, mesothelioma has also been associated with irradiation, intrapleural thorium dioxide (Thorotrast), and inhalation of other fibrous silicates, such as erionite. Some studies suggest that simian virus 40 (SV40) may act as a cofactor in the development of mesothelioma.[20]