Mesothelioma Mesothelioma, a form of cancer, develops in the organ linings. It most often affects the lung (pleura) but can also affect the lining of the abdomen (peritoneum) and heart, as well as testicles. Mesothelioma is caused by asbestos fibre exposure. Typically, symptoms don't appear until decades after exposure. Symptoms https://vimeo.com/703534646