Mesothelioma Mesothelioma, a form of cancer, occurs in the linings covering organs. It is most commonly found in the lung (pleura) but it can also affect the abdominal lining (peritoneum), heart or testicles. Exposure to asbestos fibres is the cause of mesothelioma. Typically, symptoms don't appear until decades after exposure. https://vimeo.com/705068677