Mesothelioma is cancer that attacks the mesothelium, which is a thin layer of tissue that envelopes most of the internal organs. Some organs have mesothelium, including the lungs (pleura), abdomen (abdomen), heart (pericardial), and testicles (tunica vaginalis). This cancer is classified as aggressive and many sufferers are not successfully treated.
Mesothelioma most commonly attacks the mesothelium of the lungs (called pleural mesothelioma) and the chest wall. Another type of mesothelioma less commonly encountered is peritoneal mesothelioma, which attacks the mesothelium of the abdominal cavity. Mesothelioma is different from benign mesothelioma in the chest which is also called a solitary fibrous tumor.