Asbestos exposure is the main cause of mesothelioma. After these fibers are breathed in, they travel to the ends of small air passages and reach the pleura where they cause physical damage to mesothelial cells that may result in cancer. In addition, they also cause injury to lung cells that can result in lung cancer and/or asbestosis (replacement of lung tissue by scar tissue). If swallowed, these fibers can reach the abdominal cavity where they have a role in causing peritoneal mesothelioma.
Exposure to asbestos, though mostly occupational, can also be environmental, or familial by household contamination, through the work clothes of an asbestos worker for instance.
Beginning 15 years after the onset of exposure, about 6% of asbestos workers die of mesothelioma. In one study of asbestos insulation workers, the death rate from mesothelioma was 344 times higher than in the general population. (Selifoff IJ et al. Relation between exposure to asbestos and mesothelioma. NEJM)
What is mesothelioma?
Mesothelioma is cancer of the mesothelium � the membrane that lines the interior of the chest and abdomen and surrounds the internal organs. Mesothelioma is very rare: the only known cause is asbestos exposure. It occurs when asbestos fibers � particularly those of crocidolite asbestos, which are thin and straight � penetrate the mesothelial tissue and cause inflammation; this causes a tumor to form.
Most cases of mesothelioma infect the pleura, which is the mesothelial layer that surrounds the lungs and lines the chest cavity. Pleural mesothelioma usually occurs from asbestos inhalation.
Mesothelioma can also occur in the peritoneum � the mesothelium of the abdominal cavity � or the pericardium � the mesothelial lining around the heart. Peritoneal or pericardial mesothelioma may occur as a result of either pleural mesothelioma that has migrated or from ingestion of asbestos.
What is malignant mesothelioma?
Malignant mesothelioma, a rare form of cancer, is a disease in which cancer (malignant) cells are found in the sac lining the chest (the pleura) or abdomen (the peritoneum). Most people with malignant mesothelioma have worked on jobs where they breathed asbestos.
A doctor should be seen if a person has shortness of breath, pain in the chest, or pain or swelling in the abdomen. If there are symptoms, the doctor may order an x-ray of the chest or abdomen.
The doctor may look inside the chest cavity with a special instrument called a thoracoscope. A cut will be made through the chest wall and the thoracoscope will be put into the chest between two ribs. This test, called thoracoscopy, is usually done in the hospital. Before the test, the patient will be given a local anesthetic (a drug that causes a loss of feeling for a short period of time). Some pressure may be felt, but usually there is no pain.
The doctor may also look inside the abdomen (peritoneoscopy) with a special tool called a peritoneoscope. The peritoneoscope is put into an opening made in the abdomen. This test is also usually done in the hospital. Before the test is done, a local anesthetic will be given.
If tissue that is not normal is found, the doctor will need to cut out a small piece and have it looked at under a microscope to see if there are any cancer cells. This is called a biopsy. Biopsies are usually done during the thoracoscopy or peritoneoscopy.
The chance of recovery (prognosis) depends on the size of the cancer, where the cancer is, how far the cancer has spread, how the cancer cells look under the microscope, how the cancer responds to treatment, and the patient’s age.
LAWYER FOR MESOTHELIOMA