Mesothelioma is a rare neoplasm (cancerous neoplasm) that arises from mesothelial cells lining the parietal and visceral pleura of the lungs. Mesothelium is the protective lining that covers most of the internal organs (including lungs) of the body.
The commonest site of mesothelioma is the pleura, which is the outermost lining of the lungs and the chest wall. But mesothelioma can occur at any site where mesothelial cells lining is present like peritoneum, heart etc.
The most important cause (and most likely the only cause) of mesothelioma is exposure to asbestos. Most of the patients of mesothelioma have worked on jobs where they inhaled asbestos particles, or they have been exposed to asbestos dust and fiber in one way or other. The washer men who wash cloths of persons who work with asbestos can also cause mesothelioma.
The symptoms of mesothelioma may not appear for more than 20 years of last exposure to asbestos. They may appear as late as 50 years after last exposure to asbestos, which is also a unique for a disease. The symptoms of mesothelioma include shortness of breath (due to pleural effusion), chest pain, weight loss (like any cancer), generalized weakness etc.
As mesothelioma is caused by asbestos the asbestos compensation via asbestos fund or by law-suit is an important issue in this disease. Due to the uniqueness of the disease mesothelioma (as it is caused only due to exposure to asbestos) the mesothelioma claim and compensation is very common.
Smoking does not increase (no relation with smoking and mesothelioma) the incidence of mesothelioma, unlike lung cancer.