What is the mesothelioma?
What is mesothelioma?
Mesothelioma is a malignant tumor that is located in the mesothelial cells of the pleura (at the level of the chest) or peritoneal cells in the abdomen - pleural mesothelioma being the most common. Peritoneal mesothelioma usually occurs in individuals with a history of intense and cumulative exposure to asbestos and that usually developed asbestosis. Moreover, pleural mesothelioma can occur in individuals exposed to low levels of these fibers and that have not previously developed asbestosis.
Exposure to amphibole fibers is what leads to an increased incidence of lung disease and, within this group, crocidolite is the most carcinogenic. The amosite has an intermediate toxicity. The situation, however, is controversial when it comes to chrysotile. Studies point to a relative safety of this fibrous variety when in pure form. However, when it is contaminated with tremolite (of the amphibole), it is also responsible for cases of occurrence of mesothelioma.
Cytogenetic analysis has shown that in human mesotheliomas occur non-random chromosome changes.
However, the mechanism by which there is induction of aneuploidy, ie, the gain or loss of a single chromosome, remains uncertain. Probably, the presence of fibers during mitosis in macrophages, may interfere with chromosomal segregation.
This suggests that in the mesothelial cells, the asbestos may act as initiators of mesothelioma, as they are the primary promoters of lung cancer.
The uncontrolled growth of cells starts imperceptible and, initially, does not cause discomfort. With the evolution of the disease, the first symptoms appear and are usually diffuse pain in the chest and less prevalence, shortness of breath and cough.
In general, the affected people die within 12 to 18 months after diagnosis, because the therapy is extremely difficult and inadequate.