Malignant mesothelioma (me-zoe-thee-lee-O-muh) is a type of cancer that occurs in the thin layer of tissue that covers the majority of your internal organs (mesothelium).Mesothelioma is an aggressive and deadly form of cancer. Mesothelioma treatments are available, but for many people with mesothelioma, a cure isn't possible.Doctors divide mesothelioma into different types based on what part of the mesothelium is affected. Mesothelioma most often...