Types of Mesothelioma

Asbestos lung cancer is a group of diseases related to asbestos exposure. Asbestos is a naturally occurring mineral that has been mined, processed, and used for over 6,000 years. The two most common diseases related to asbestos lung cancer are asbestosis and mesothelioma, with pleural mesothelioma being the most common form of mesothelioma. Both mesothelioma and asbestosis are associated with the inhalation of asbestos and subsequent inflammation caused by the lodging of asbestos in the lungs.
Mesothelioma
Malignant mesothelioma is a type of asbestos lung cancer. Mesothelioma is a rare form of cancer that results from asbestos becoming lodged in the lung lining. However, unlike asbestosis, mesothelioma occurs in the serous lining of the lung, which is the lining surrounding the outside of the lungs. Also unlike asbestosis, mesothelioma is malignant, while asbestosis is benign. Malignant means that the growths in the lung serous membranes related to mesothelioma are cancerous, can grow rapidly and spread to other organs. Asbestosis, on the other hand, does not spread to other organs. When cancer tumors grow and then spread to other organs, this is called metastasis.
Pleural Mesothelioma
Mesothelioma can affect different organs in the body, not just the lungs. When mesothelioma occurs in the lungs, it is called pleural mesothelioma. When this disease occurs in the heart lining it is called pericardial mesothelioma, and when it occurs in the abdomen it is called peritoneal mesothelioma. Asbestos exposure is thought to be the primary cause for these other types of mesothelioma.
The time line between asbestos exposure and the onset of pleural mesothelioma is very long, 30 to 40 years. Pleural mesothelioma can also be detected by x-rays, but the diagnosis of pleural mesothelioma has to be confirmed with a biopsy. The treatment of pleural mesothelioma is the same as for other cancers, but the disease is very aggressive and most treatments do not slow the disease’s progression. The life expectancy of those diagnosed with pleural mesothelioma is very short, less than a year.
Asbestosis
Asbestosis is a disease where exposure to asbestos can cause scarring of the lungs and lead to asbestos lung cancer; however, it is not a type of lung cancer. Asbestos fibers are tiny, yet durable. When they are inhaled, the lungs' natural filtration process is unable to eliminate the fibers from the air, allowing asbestos to enter the very sterile inner reaches of the lung cavities. When these fibers become lodged in the lining of the lung, inflammation begins and eventually leads to scarring of the lung lining.
The time line between when the asbestos enters the lungs and when the scarring begins can be as many as ten years. Eventually, if enough scarring occurs in the lungs, fibrosis develops in the lung lining. Fibrosis is defined as the development of excess fibrous connective tissue in an organ. This connective tissue cripples the areas of the lungs that it invades. Thus, over time, large areas of the lung are unable to function because of the fibrosis. Similar to pleural mesothelioma, the total time line between exposure to asbestos and the development of large areas of fibrosis can be as long as 30 or 40 years.
Asbestosis is normally detected with an x-ray showing the large fibrous growths in the lungs. The initial symptom is difficulty in breathing. There is no cure for asbestosis and eventually the fibrous tissue can spread completely throughout the lungs and make it impossible to breath. Congestive heart failure is a common cause of death related to asbestosis. The heart becomes overworked in its attempt to push enough blood through the lungs to carry sufficient oxygen to the rest of the body.