How Does Asbestos Cause Mesothelioma?

The main way by which asbestos fibers get into the body is through the respiratory system. Fibers released into the air are inhaled by the exposed individuals and are transported into the deep parts of the lungs.

Asbestos fibers that have been lumped into heavier particles of plaster, concrete or paint are often expelled through coughing and rarely get to the deep parts of the lungs. Post- mortem examinations of lungs of dead victims of mesothelioma have revealed that asbestos fibers tend to accumulate near the bottom lobes of the lungs, in the gutter of the thoracic cavity and on the surface of the diaphragm.

These asbestos fibers migrate from the lung spaces called the alveoli into the intra- pleural space, within the mesothelial layer of the space. This was described by many physicians as a “clearing” of the lungs. It has also been hypothesized that asbestos fibers can be swallowed or may enter directly by piercing the skin. It is not known why some patients develop peritoneal mesothelioma rather than the more common pleural based disease.

The clearing of the lungs is directly connected to the two primary theories about how injury is caused by asbestos.

The first theory postulates that the asbestos fibers pierce the tissue walls of the pleural space (and sometimes the peritoneal space via the stomach or the diaphragm) and cause tissue damage which creates an inflammatory immune response.

The second theory states that the asbestos fibers are so small that they begin to interact with mesothelial cells at a molecular level, interrupting cell replication and/or damaging the cellular DNA during mitosis, or cell division.

The migration of the asbestos fibers out of the alveoli is possible because of the small size of the asbestos fibers. This allows them to pierce the cell walls and migrate between cell boundaries into the mesothelial lining of the pleural cavity or even into the intrapleural space. There, they sometimes penetrate the diaphragm and make their way into the abdomen or the testes leading to abdominal and testicular mesothelioma.

Whenever these fibers migrate, they leave a trail of damaged or compromised cells behind. They usually elicit an inflammatory response which leads to the formation of malignant tumor cells of mesothelioma. The response to this damage varies by individual and invariably involves the immune system. Evidence for the response is found in the irritation and destruction of cells and the creation of scar tissue at the site of the injury.

This process can be quite significant in the case of heavy asbestos exposure and can lead to major impairment of the lungs as a crust or plaque of fibrous scar tissue forms over the affected areas. Microscopic examination of this material has often found asbestos fibers entombed in the nodules and layers of tissue and has been used as undeniable evidence for the asbestos connection as a cause for the injury in asbestos related diseases like mesothelioma.

About the Author: Bello kamorudeen.


Posting Komentar