othelioma: Types, Risk Factors, Symptoms and Treatment

Mesothelioma is a rare type of malignant cancer that is usually caused by exposure to asbestos. The cancer affects the mesothelium which is a protective membrane that covers most of the internal organs of the body. The mesothelium is known by different names depending on where it is found

 in the body. When it covers the lungs and chest cavity, it is known as the pleura; over the heart, it is called the pericardium; and in the abdominal cavity it is called the peritoneum. It is also found in other places such as the testes and uterus (womb). The mesothelium normally secretes a lubricating fluid that allows organs to move easily against nearby structures.

How Mesotheliomas Occur

Mesotheliomas usually begin in the lungs or abdomen before they spread to other parts of body (they usually do not spread to the brain, bone or adrenal glands). The mechanism by which mesotheliomas occur has not been properly elucidated. It is possible that deposition of asbestos fibers in the mesothelium causes diverse interactions with the mesothelial cells and induces reactions with the defensive mechanisms of the body. These cause the mesothelium to become abnormal and divide without control and order. It then metastasizes to other parts of the body.

Types of Mesothelioma

1. Epithelioid mesothelioma: This is the most common type of mesothelioma and usually has a better outcome than other types.

2. Mixed or Biphasic mesothelioma: This is the second most common type. It has features of epithelioid and sarcomatoid mesotheliomas.

3. Sarcomatoid or Fibroid mesothelioma: This is the least common type.

Mesotheliomas are also named according to tissue from which they originate. When they originate in the pleura, they are called pleural mesotheliomas; when they occur in the pericardium, they are called pericardial mesotheliomas, and so on.

Risk Factors for Mesothelioma

Mesothelioma occurs in a person who has been exposed to asbestos such as from inhaling asbestos particles or from exposure to asbestos dust or fibers. It is occurs more commonly in people who work with asbestos but there are also other risk factors for mesothelioma