What Is Malignant Mesothelioma?

Malignant mesothelioma is a disease in which malignant (cancer) cells are found in the mesothelium, which is a thin layer of tissue that covers most organs in the body. Mesothelioma most commonly affects the pleura (the thin layer of tissue that lines the chest cavity and covers the lungs) or the peritoneum (the thin layer of tissue that lines the abdomen and covers most of the organs in the abdomen). This article discusses malignant mesothelioma of the pleura.