Mesothelioma Mesothelioma is a type of cancer that forms in the linings that cover organs. It most often affects the lungs (pleura) but it can also affect the abdomen's lining (peritoneum), heart or the testicles. Mesothelioma is caused by asbestos fibre exposure. Typically, symptoms don't appear until decades after exposure. https://vimeo.com/704909237