We have many different cells in our body. Each organ cell is unique to that particular organ. For example, lung cells look different from the cells of the colon, mesothelium, brain, liver, and breast.
Normally cells grow, divide, and produce new cells that keep us healthy, and then they die in a predictable way. Cancer occurs when the cells grow out of control and do not die, these cells form a mass of tissue that is called a tumor. They can invade and damage nearby tissues and organs. Cancer cells can also spread from their original site to other parts of the body.
Mesothelium cells make up a membrane/lining that covers and protects the lungs (called the pleura), heart (called the pericardium), as well as abdominal cavity (called the peritoneum). Malignant Mesothelioma is when cancer cells are found in the mesothelium.
Malignant Pleural Mesothelioma (MPM) occurs when the pleural mesothelium (lung lining) is cancerous. Eighty percent of all mesothelioma cases affect the lining of the lungs.