Mesothelioma Types

Most commonly known Mesothelioma Types are:

• Pleural Mesothelioma
• Peritoneal Mesothelioma
• Other Mesotheliomas
• Benign Mesotheliomas

The section below summarizes each type of mesothelioma.

Pleural mesothelioma

Pleural mesothelioma is of two kinds: (1) diffuse and malignant (cancerous), and (2) localized and benign (non-cancerous.)

Benign mesotheliomas can often be removed surgically, are generally not life-threatening, and are not usually related to asbestos exposure. Malignant mesotheliomas, however, are very serious. Fortunately, they are rare - about two thousand people are diagnosed with mesothelioma in the U.S. each year.

Pleural mesothelioma is a cancer of the cells that make up the pleura or lining around the outside of the lungs and inside of the ribs. Its only known cause in the U.S. is previous exposure to asbestos fibers, including chrysotile, amosite or crocidolite. This exposure is likely to have happened twenty or more years before the disease becomes evident, since it takes many years for the disease to "incubate." It is the most common type of mesothelioma, accounting for about 75% of all cases.

Peritoneal mesothelioma

Many of the organs in the abdomen are enveloped by a thin membrane of mesothelial cells, known as the peritoneum. Peritoneal mesothelioma is a tumor of this membrane. Its only known cause in the U.S. is previous exposure to asbestos, but it can be many years after exposure before the disease appears. Peritoneal mesotheliomas account for about one-fifth of all mesotheliomas.

Like pleural mesothelioma, peritoneal mesothelioma can be either benign or malignant. This discussion is only about malignant peritoneal mesothelioma.

Benign pleural diseases

There is much confusion about the different types of benign (or non-cancerous) pleural diseases, mainly because different researchers and doctors use different words to describe the same things, or the same words to describe different things.

This is a discussion about pleural diseases that are related to asbestos exposure, are not malignant (like mesothelioma), and exist only in the pleura. They can be divided into three groups: plaques, thickening, and effusions.

Pleural plaques are small, hard, plate-like surfaces on the pleura, similar to arteriosclerosis in coronary arteries. They are caused by asbestos fibers that invade the pleura from the lungs. Medical researchers do not fully understand the underlying processes of why asbestos fibers cause plaques to develop.

Other Mesotheliomas

While the great majority of mesotheliomas are in either the pleura or the peritoneum, malignant mesotheliomas sometimes occur in other parts of the body, including the testicles (a variety of peritoneal mesothelioma) and the heart (a variety of pleural mesothelioma.) These are also caused by exposure to asbestos fibers.

Benign mesotheliomas occur less frequently than malignant mesotheliomas. They are generally thought to be unrelated to asbestos exposure. Two thirds of benign mesotheliomas occur in females