What is Mesothelioma?

Answer:

Mesothelioma is a rare form of cancer that is almost always caused by previous exposure to asbestos.
Causes of Mesothelioma
Before the grave dangers of asbestos were known, and even for years after the dangers were known, asbestos was used in literally thousands of products that humans and animals encounter every day - particularly in building components such as ceiling and floor tiles, walls, bricks and stucco, and in automotive parts such as brakes and clutches.
People who worked in the asbestos industry or in fields in which asbestos is used as a component of a product are most at risk for mesothelioma. Many individuals who have mesothelioma labored for years or even decades in jobs that required frequent contact with asbestos. When this mineral is mined, processed, woven, sprayed or otherwise manipulated, its microscopic fibers can be released into the air, where they may be inhaled, initiating the development of mesothelioma.
Types of Mesothelioma
Mesothelioma can attack the pleural lining around the lungs. It can also attack the peritoneum, a tissue that surrounds the GI tract. Mesothelioma can attack the stomach lining, other internal organs, or even the pericardium (the tissue sac covering the heart). Thus, mesothelioma can be generally classified into the following types:

• Pleural - 75% of all mesothelioma cases
• Peritoneal - 10%-20%
• Pericardial - 5%

Mesothelioma can also be classified by the cancer type rather than the location of the cancer:

• Epithelioid - most common, best survival rate
• Sarcomatoid - most severe, but more rare
• Mixed/biphasic - a mixture of epithelioid and sarcomatoid cancer

Mesothelioma, there are two, 1. Pleural mesothelioma is pleural primary tumor, a localized (mostly benign) and diffuse (all malignant) points. Diffuse malignant mesothelioma is one of the worst prognosis breast tumors. Most patients in the 40-70 years old, more men than women. 2. Peritoneal mesothelioma is the primary peritoneal mesothelial cells in the tumor. Does not have the characteristic clinical manifestations, common signs and symptoms include: abdominal pain, ascites, abdominal distention and abdominal mass, and so on. Peritoneal mesothelioma accounts for about 20% of all mesothelioma cases, can occur in 2-92 years, mean age was 54 years old, of which about 63% of cases in the 45-64 years of age, children are rarely sick.

Source：http://www.mesothelioma-cancer-usa.info/?p=102