Mesothelioma is a rare type of cancer (malignancy) that most frequently arises from the cells lining the sacs of the chest (the pleura) or the abdomen (the peritoneum). Pleural mesothelioma is the most common form, often becoming apparent with symptoms in the chest area such as chest pain, cough, and/or shortness of breath. Shortness of breath often occurs due to a large pleural effusion (fluid in the thoracic cavity). Peritoneal mesothelioma is much less common. This can affect the organs in the abdomen, and its symptoms are related to this area of the body, that is, abdominal swelling, nausea, vomiting, and bowel obstruction. The rarest form of mesothelioma is pericardial mesothelioma, which involves the sac surrounding the heart.
There are two major cell types of mesothelioma, epithelial and sarcomatoid. Sometimes both of these cell types can be present, also referred to as biphasic. The sarcomatoid type is rarer and occurs in only about 15% of cases; it portends a poorer prognosis. In very rare cases, mesothelioma can originate from benign, non-malignant cells. Surgery cures this so-called benign mesothelioma.
What causes mesothelioma?
Most people with malignant mesothelioma have worked on jobs where they breathed asbestos. Usually, this involves men over 40 years of age. Others have been exposed to asbestos in a household environment, often without knowing it. The number of new cases of mesothelioma has been relatively stable since 1983, the same time that the U.S. Occupational Safety and Health Administration (OSHA) instituted restrictions on asbestos. In Europe, the number of new cases of mesothelioma continues to rise.
How Long Does It Take For Mesothelioma To Develop
According to Mayo Clinic, when asbestos dust is inhaled or swallowed, the asbestos fibers will settle in the lungs or in the stomach, where they can cause irritation that may lead to mesothelioma. Exactly how this happens isn’t understood. It can takes between 20 to 60 years or more for mesothelioma to develop after asbestos exposure. Most people with asbestos exposure never develop mesothelioma. This indicates that other factors may be involved in determining whether someone gets mesothelioma. For instance, you could inherit a predisposition to cancer or some other condition could increase your risk.
According to the American Cancer Society the risk of mesothelioma does not go down over time after the exposure to asbestos stops. The risk appears to be lifelong they include
Zeolites are minerals chemically related to asbestos. An example is erionite, which is common in the rocks and soil in parts of Turkey. High mesothelioma rates in these areas are believed to be caused by exposure to this mineral. In the United states, erionite has been detected in Nevada, Oregon, Utah, Arizona, Montana, and South Dakota.
There have been a few published reports of mesotheliomas that developed after people were exposed to high doses of radiation to the chest or abdomen as treatment for another cancer. Although the risk of mesothelioma is higher in patients who have been treated with radiation, this cancer is still rare in these patients.
Some studies have raised the possibility that infection with simian virus 40 (SV40) might increase the risk of developing mesothelioma. But most experts agree that at this time we still don’t know if SV40 is responsible for some mesotheliomas. This important topic is still being researched.
The risk of mesothelioma increases with age. Mesothelioma can occur in young people (even children), but it’s rare in people under age 45. About 2 out of 3 people with mesothelioma of the chest are 65 or older.
Mesothelioma is much more common in men than in women. This is probably because men have been more likely to work in jobs with heavy exposure to asbestos.
A mutation or change in the gene called BAP1 can be passed in families and has been linked to mesothelioma. But BAP1 mutations are rare. ALSO READ: Can A Person Get Mesothelioma From Working With Fiberglass?