Malignant Mesothelioma
Malignant mesothelioma affects the lining or membranes of certain large
cavities in the body. These cavaties are called serous cavities. They
contain certain major organs like the heart, lungs, abdomen and others.
The membranes that surround these cavities are called the serous membranes
which protect these major organs from the friction and abrasion that occur
as the organs move against each other during typical daily functioning,
such as breathing and heart beating. The serous membranes derive from
specialized cells called mesothelial cells. These cells form to create
the mesothelium, which is the major tissue layer of the serous membranes.
Cancer that occurs in the mesothelium tissue is called mesothelioma.
Three types of Malignant Mesothelioma:
Peritoneal mesothelioma, in the peritoneum or membrane surrounding
the abdomen. A rare form of peritoneal mesothelioma can also affect the
male testicles, because the lining around the scrotum is an extension
of the peritoneum.
Pericardial mesothelioma, in the perdicardium or lining surrounding
the heart.
Pleural mesothelioma, which is the most common form of malignant
mesothelioma and affects the lining of the lung cavity.
All mesotheliomas are now considered to be malignant, or cancerous. They
start as a localized tumor and spread rapidly to include most of the surrounding
tissues and organs.
Most cases of malignant mesothelioma are associated with a previous exposure
to fibrous minerals, of which asbestos is the most important. There is
now indisputable evidence of the role of these fibers in the development
of this disease. This has been demonstrated in animal experiments and
many other experiments. Not everyone who is exposed to asbestos fibers
has developed malignant mesothelioma, suggesting that other factors may
also be involved.
Malignant mesothelioma is rare but it is a serious and deadly disease.
It is often in the advanced stages when it is detected, so the outlook
for the patients is not as good as it is for the cancers that are detected
earlier. The average survival time after detection is 1 to 2 years.
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