Stacy R. Beck Houston
LS 120, Lab LS 111
Bio 20, Anatomy Andy Hufford
May 6, 2003
Asbestos is the name given to a group of six different fibrous
minerals (amosite, chrysotile, crocidolite, and the fibrous varieties of
tremolite, actinolite, and anthophyllite) that occur naturally in the
environment. Asbestos minerals have separable long fibers that are strong
and flexible enough to be spun and woven and are heat resistant. Because of
these characteristics, asbestos has been used for a wide range of
manufactured goods, mostly in building materials (roofing shingles, ceiling
and floor tiles, paper products, and asbestos cement products), friction
products (automobile clutch, brake, and transmission parts), heat-resistant
fabrics, packaging, gaskets, and coatings. Some vermiculite or talc
products may contain asbestos.
It is known that breathing asbestos can increase the risk of cancer in
people. There are two types of cancer caused by exposure to asbestos: lung
cancer and mesothelioma.
Mesothelioma is a cancer of the thin lining surrounding the lung
(pleural membrane) or abdominal cavity (the peritoneum). Cancer from
asbestos does not develop immediately, but shows up after a number of
years. Studies of workers also suggest that breathing asbestos can increase
chances of getting cancer in other parts of the body (stomach, intestines,
esophagus, pancreas, and kidneys), but this is less certain.
Early identification and treatment of any cancer can increase an
individual’s quality of life and survival.
Malignant mesothelioma attacks the lining of the lungs, heart and/or
Mesothelioma strikes over 3,000 people each year. The disease is
almost exclusively caused by asbestos exposure. Asbestos is a known toxin
that irresponsible companies continued to market for decades in the face of
scientific evidence proving its danger.
Mesothelioma is a highly aggressive cancer that comes in two forms
(peritoneal or pleural) and is almost always caused by asbestos exposure.
Mesothelioma is the term used to describe a cancerous tumor that involves
the mesothelial cells of an organ. Mesothelial cells are cells that form a
protective lining over the lungs, heart and abdominal organs. The most
common type of mesothelioma is pleural mesothelioma. The pleura are a thin
membrane found between the lungs and the chest cavity. It provides a
lubricated surface so that the lungs do not rub and chafe against the chest
Virtually all cases of mesothelioma are related to inhaling of
asbestos fibers. There are about 3,000 cases per year (mostly men over the
age of 40) and there will be about 300,000 cases before 2030.
Mesothelioma usually spreads rapidly through the mesothelial cells to
the heart and abdominal organs. The life span is typically 24 months after
diagnosis, but it depends on what stage the cancer is detected, the health
of the patient and other factors. Although asbestos exposure causes
mesothelioma, it has a latency period after exposure that could last 15 to
50 years. This means that someone who worked in a factory with asbestos 40
years ago could be developing mesothelioma now. Anyone who knows they were
exposed to loose asbestos fibers should be tested regularly for
The onset of mesothelioma is usually very slow. The first symptom is a
constant pain in the chest. This pain is later accompanies by difficulty
breathing due to an accumulation of fluid in the chest. Other symptoms
include coughing, fever and weight loss. Mesothelioma can be by your doctor
with a diagnosed with a chest CT-scan.
Mesothelioma advances in 4 stages:
Stage I – the tumor is limited to the area of the lining of the lung
and usually limited to only one side of the chest. Stage II – the tumor
extends to other organs within the chest cavity, such as the heart or lymph
nodes in the chest. Stage III – the tumor expands to the other side of the
chest or it spreads into the abdominal organs. The lymph nodes outside the
chest are affected. Stage IV -the cancer spreads to different parts of the
body far outside the chest area (liver, brain, bone, etc.)
Mesothelioma is an extremely deadly disease. The average survival
time is about one year from date of diagnosis. About 20% of patients who
find their cancer early and treat it aggressively will reach the five-year
Mesothelioma is nearly always related to Asbestos exposure. Asbestos is an
extremely dangerous material and low exposure levels can trigger
Mesothelioma. This means that even family members of asbestos workers are
at risk because of the asbestos fibers brought into the home on their
Scientists have known about asbestos’s carcinogenic (cancer-causing)
properties since the 1930’s, but asbestos was a cheap insulator and
fireproofing material. Corporations continued to put workers and their
families at risk for decades after its lethality was discovered.
If you have Mesothelioma, you are invariably a victim of asbestos, a
material whose danger was known as early as the 1930s. Many asbestos
manufacturers and corporate users of asbestos materials ignored the
scientific data showing asbestos’ lethality. In the end, workers who had to
work with the material were the ones who suffered
Originally, asbestos was viewed as a miracle material. It is
inexpensive and an excellent insulator and fireproof material. However,
around the turn of the century, researchers noticed a large numbers of
deaths and lung problems in asbestos mining towns.
After diagnosis, your doctor or oncologist (cancer specialist) will
provide you with information on the treatment options that are available to
you. They are, Surgery, Radiotherapy, Chemotherapy, and Alternative
There are two types of surgeries, those that actually remove the
cancer itself and those that help alleviate pain and suffering (symptoms).
If the cancer has not spread to too many organs, surgery can be used to
remove part of the lining of the chest or abdomen. The purpose of this
surgery is to simply remove the cancer cells from the body by removing the
tissues with large numbers of cancer cells. More serious operations can
remove large parts of the lung or the diaphragm. The more serious
operation requires the patient to be in excellent health.
If the cancer has spread to several organs, it is impossible to remove
all of the tissue infected with cancer. In this case, surgery can only be
used to relieve symptoms. One operation is a thoracentesis, where fluid in
the chest is removed by placing a needle into the chest cavity, may help to
improve comfort and breathing. This procedure does nothing to cure the
cancer, only to relieve the symptoms.
Radiation therapy is sometimes used as the main treatment of
Mesothelioma in some patients, especially those whose general health is too
poor to undergo surgery. Radiation may also be used to supplement surgery.
Chemotherapy is the use of drugs for treating cancer. The drugs can be
swallowed in pill form or a needle into a vein or muscle can inject them.
The drug enters the bloodstream and circulates throughout the body to reach
and destroy the cancer cells.
While surgery and radiation (above) can target specific areas,
chemotherapy targets the entire body and can kill normal cells. This means
that chemotherapy can have severe side effects. Chemotherapy can also be
injected directly into specific locations, such as the chest. Chemotherapy
can be used in combination with a variety of drugs to increase the total
effect. Chemotherapy is often used in combination with other treatments,
such as surgery.
Many alternative therapies are available for Mesothelioma. These
therapies generally are not as well tested as the above therapies, but at
any time a new discovery or study could make one of these therapies the
standard in Mesothelioma treatment.
These therapies change the genetic structure of organisms to defeat
Mesothelioma. Gene therapies are still in development and few have shown
practical benefit to date.
This therapy involves using a drug to make cancer cells sensitive to a
particular light wavelength. The cells would then be exposed to that light
wavelength to kill the Mesothelioma cells. This form of treatment is still
controversial and experimental, but improvements may occur.
New treatments are being researched all the time. Organizations such
as the National Cancer Institute and the American Cancer Society are
participating in clinical trials to test how well new drugs and therapies