How Does
Mesothelioma Develop?
A number of studies have explored how asbestos causes
mesothelioma. In 2012, mesothelioma expert Dr. Michele Carbone, director of
thoracic oncology at the University of Hawaii Cancer Center, co-wrote a
scientific article detailing multiple ways asbestos may damage the body,
including the creation of inflammatory chemicals that cause direct genetic
damage.
It usually takes heavy, long-term exposures to
asbestos for a related cancer to develop, but even minor exposures can be
harmful. Activities that disturb asbestos-containing products release toxic
fibers into the air.
Mesothelioma has a dose-response relationship to
asbestos, which means higher doses of asbestos exposure lead to a greater risk
of developing mesothelioma. When it comes to asbestos, high concentrations of
fibers and long durations of exposure amount to a greater risk of developing an
asbestos-related disease.
Once inhaled, the body has a hard time getting rid of
the sharp, sometimes jagged fibers, and they build up in the lungs or abdomen
over time. Many years after the first exposure, these fibers may cause
cancerous changes.
Cancer starts in mesothelial cells, which comprise the
protective membranes that cover the lungs, abdomen and heart.
Diagram of someone breathing in asbestos
Possible
Theories for Asbestos-Related Tumor Development
·
Inflamed Cells
Fibers inflame and
irritate mesothelial cells, which leads to irreversible scarring, cellular
damage and cancer.
·
Genetic Changes
Fibers enter
mesothelial cells and disrupt their life cycle. This can cause genetic changes
that lead to cancer.
·
Cancerous Mutations
Asbestos causes the
production of free radicals, which are molecules that damage DNA and cause
healthy cells to undergo cancerous mutations.
·
Uncontrolled Growth
The fibers can trigger
the production of oncoproteins, which block genes that protect cells from
growing uncontrollably and forming tumors.
The common ground of these theories: Asbestos causes
damages that change a cell's natural cycle.
Every healthy cell has genes that safeguard against
cancer. Once asbestos blocks this function, cells can divide uncontrollably,
spreading throughout the body and forming tumors. These tumors are a patient's
main source of symptoms.
While all types of asbestos cause mesothelioma,
certain types, such as crocidolite and amosite, are more carcinogenic than
others. Researchers believe the varying chemical composition of the different
asbestos types is what makes one type more carcinogenic than another.
Keep in mind that about 20 percent of people
occupationally exposed to asbestos will go on to develop a related health
condition.
The vast majority of people who work with asbestos
will not develop a disease. Individual factors like genetics play a role in
mesothelioma development, while factors such as smoking cigarettes play a role
in the development of asbestos-related lung cancer.