W h a t i s M e s o t h e l i o m a ?
Mesothelioma is a rare type of cancer that develops in
the mesothelial cells that lines many organs and body
cavities. The mesothelium (composed of mesothelial cells)
is the membrane that lines three of the body’s cavities,
and depending on what cavity it lines it is given a specific
name: the thoracic cavity (pleura), abdominal cavity (peritoneum),
and the heart sac (pericardium).
The mesothelium that covers the internal organs is called
the visceral mesothelium, while the layer that covers the
body wall is called parietal mesothelium.
Mesothelium tissue also surrounds the male internal
reproductive organs and covers the internal reproductive
organs in women.
Mesothelioma is an aggressive cancer of this mesothelium,
in which cells of the mesothelium become abnormal and
divide uncontrollably and without order. They can invade
and damage nearby tissues and organs. Most cases of
mesothelioma begin in the thoracic cavity (pleura) or the
abdominal cavity (peritoneum).
Approximately 2,000 to 3,000 cases of mesothelioma are
diagnosed each year in the United States, comprising
around 3 percent of all cancer diagnoses. This cancer occurs
more frequently in men than in women, about four times more frequent. All forms of mesothelioma, except for benign mesothelioma,
are invariably fatal. The prognosis for mesothelioma is almost always poor and most studies report a median survival of
less than one year, but the prognosis really depends on how early it is diagnosed and how aggressively it is treated
Mesothelioma is almost exclusively caused by asbestos exposure. Asbestos is a naturally-occurring fibrous substance that was
widely used in the twentieth century in a number of different industries. Popular because of its durability, fire resistance, and
insulating properties, it was regularly used in the manufacture of several thousand different products, up until the time that
asbestos warnings were issued in the mid-1970s. It is estimated that approximately 80 to 90 percent of mesothelioma cases are
linked to asbestos exposure.
The exact way in which asbestos causes mesothelioma is not well understood, though doctors and researchers have put forth
many hypotheses. What is apparent, however, is that any length of exposure to asbestos can be hazardous and may result in the
development of asbestos-related disease later in life.
the mesothelial cells that lines many organs and body
cavities. The mesothelium (composed of mesothelial cells)
is the membrane that lines three of the body’s cavities,
and depending on what cavity it lines it is given a specific
name: the thoracic cavity (pleura), abdominal cavity (peritoneum),
and the heart sac (pericardium).
The mesothelium that covers the internal organs is called
the visceral mesothelium, while the layer that covers the
body wall is called parietal mesothelium.
Mesothelium tissue also surrounds the male internal
reproductive organs and covers the internal reproductive
organs in women.
Mesothelioma is an aggressive cancer of this mesothelium,
in which cells of the mesothelium become abnormal and
divide uncontrollably and without order. They can invade
and damage nearby tissues and organs. Most cases of
mesothelioma begin in the thoracic cavity (pleura) or the
abdominal cavity (peritoneum).
Approximately 2,000 to 3,000 cases of mesothelioma are
diagnosed each year in the United States, comprising
around 3 percent of all cancer diagnoses. This cancer occurs
more frequently in men than in women, about four times more frequent. All forms of mesothelioma, except for benign mesothelioma,
are invariably fatal. The prognosis for mesothelioma is almost always poor and most studies report a median survival of
less than one year, but the prognosis really depends on how early it is diagnosed and how aggressively it is treated
Causes of Mesothelioma
widely used in the twentieth century in a number of different industries. Popular because of its durability, fire resistance, and
insulating properties, it was regularly used in the manufacture of several thousand different products, up until the time that
asbestos warnings were issued in the mid-1970s. It is estimated that approximately 80 to 90 percent of mesothelioma cases are
linked to asbestos exposure.
The exact way in which asbestos causes mesothelioma is not well understood, though doctors and researchers have put forth
many hypotheses. What is apparent, however, is that any length of exposure to asbestos can be hazardous and may result in the
development of asbestos-related disease later in life.
Types of Mesothelioma
There are five known types of mesothelioma. Four of these are malignant cancers, and one is a benign condition.
Pleural Mesothelioma:This type of mesothelioma develops in the lining of the lungs, known as the pleura. It is the most
common form of malignant mesothelioma, with around 70 percent of cases being pleural in origin.
Peritoneal Mesothelioma: This form of mesothelioma develops in the lining of the abdominal cavity, known as the peritoneal
membrane. Approximately 25 percent of mesotheliomas are of this type.
Pericardial Mesothelioma: This form of mesothelioma develops in the lining of the heart, known as the pericardium. About 5
percent of all mesothelioma cases are pericardial.
Testicular Mesothelioma: This is the rarest type of malignant mesothelioma; to date, there have been less than 100 recorded
cases. Testicular mesothelioma develops in the tunica vaginalis of the testicles.
Benign Mesothelioma: The benign form of mesothelioma most commonly develops in the pleura. This is the only form of
mesothelioma for which full cure and recovery is a probable outcome, though it may be a precursor of future
asbestos-related problems.
Mesothelioma Symptoms and Diagnosis
Mesothelioma is difficult to diagnose, largely due to the fact that it remains latent in the body for up to five decades and is
usually not diagnosed until its late stages.
The most common symptoms of pleural mesothelioma are shortness of breath, chest pain, and persistent cough. However,
some patients may not show any symptoms at all. A frequent sign is pleural effusion (water in the lungs).
Some symptoms of peritoneal mesothelioma include weight loss, abdominal pain and swelling and bowel obstruction. If the
cancer has spread to other parts of the body, some other common symptoms may include trouble swallowing, swelling of the
neck or face, blood clotting problems, anemia and fever.
Also, diagnosis may be difficult due to the non-specific nature of most mesothelioma symptoms, which often resemble symptoms
of less serious diseases.
The process of diagnosis usually begins with a compilation of the patient’s full medical and work history, including any exposure
to asbestos. A medical examination is performed and if a problem is suspected, one or more diagnostic tests are ordered. These
typically include medical imaging tests such as x-rays, CT and MRI scans, as well as biopsy procedures that test samples of fluid
and tissue for the presence of cancer cells. Diagnostic tests are also used to determine how far the cancer has advanced, and
whether it has spread to other locations in the body.
Mesothelioma Treatment
Mesothelioma treatments can be divided into two main categories: curative treatments and palliative treatments. Curative treatments
are those carried out in an attempt to remove all cancer cells and cure the disease. Palliative treatments are designed to
ease pain and make a patient more comfortable.
Treatments for mesothelioma include conventional treatments such as surgery, chemotherapy and radiation therapy, as well as
experimental procedures, including immunotherapy and gene therapy.
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