Mesothelioma is a form of cancer that is almost always caused by previous exposure to asbestos.   In this disease, malignant cells develop in the mesothelium, a protective lining that covers most of the body’s internal organs.

 Its most common site is the pleura (outer lining of the lungs and chest cavity), but it may also occur in the peritoneum (the lining of the abdominal cavity) or the pericardium (a sac that surrounds the heart).

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or have been exposed to asbestos dust and fibre in other ways, such as by washing the clothes of a family member who worked with asbestos, or by home renovation using asbestos cement products. Unlike lung cancer, there is no association between mesothelioma and smoking.

MESOTHELIOMA is characterized by having a relatively long latency period, which means that symptoms do not develop until 10 to 50 years after exposure to asbestos. The average age at which symptoms usually begin to appear is around 60 years old. It is estimated that about 3,000 to 4,000 cases of mesothelioma are diagnosed each years in the US. The number of cases reported each year is increasing.