Mesothelioma Mesothelioma is a type of cancer that forms in the linings of organs. It usually affects the lungs (pleura) but it can also affect the abdominal lining (peritoneum), heart or testicles. Exposure to asbestos fibres can be the cause of mesothelioma. Typically, symptoms don't appear until decades after exposure. https://vimeo.com/704936425