Mesothelioma is a cancer which, in over 80% of cases, develops on the outer lining of the lungs, medically known as pleura. Accordingly, the formal name of this type is pleural mesothelioma. However, it can also affect the lining of the abdomen (peritoneal mesothelioma) and the lining of the heart (pericardial mesothelioma).
The causal relationship between asbestos exposure and mesothelioma is indisputable. Since 1959, when the first paper linking mesothelioma to asbestos exposure was published by three South African physicians, a series of well-grounded medical studies supporting the connection have been emerging throughout the world. According to the International Agency for Research on Cancer, each of the six asbestos types can cause mesothelioma, as the mineral is always carcinogenic. Moreover, the agency states that the length of asbestos fibers has no influence on mesothelioma risk. Nevertheless, the risk of developing mesothelioma was found to increase with the amount of asbestos fibers inhaled, as well as with the duration of exposure.
A key aspect concerning mesothelioma is latency period. Similarly to the other diseases stemming from asbestos exposure, it usually takes several decades for this cancer to set in. Mesothelioma occurs in 20 to 50 years from the first asbestos exposure. The reason for this long latency period pertains to the way cancer develops once asbestos fibers become lodged in the lining of the lungs. Although they are carcinogenic and very irritating to internal tissue, asbestos fibers produce inflammation and scarring gradually. Over time, these symptoms will give way to malignant tumors, which indicates the onset of mesothelioma. After the onset per se, cancer tends to progress very rapidly and while mesothelioma advances, it also becomes more and more resistant to treatment. Consequently, timely detection is critical and can improve prognosis to a great extent.
Unfortunately, only a small portion of mesothelioma patients are diagnosed when their cancer is in early stages, hence the poor prognosis associated with this disease. The average life expectancy for mesothelioma is 12 months. Roughly 55% of patients survive longer than 6 months, whereas barely 35% of them live for more than one year. As people suffering from it rarely experience symptoms, mesothelioma is typically discovered in severe stages, when treatment is no longer effective. However, it is important to keep in mind that early diagnosis can prolong survival considerably, as well as lead to a more favorable prognosis. For this reason, if you have a history of occupational asbestos exposure, we strongly encourage you to undergo a screening test annually, which – in the regrettable event that you develop mesothelioma – will help your physician detect it on time.
While this cancer is not typically accompanied by clear symptoms, these are some of the most common signs people suffering from early-stage mesothelioma might notice:
- a persisting dry cough
- shortness of breath
- chest pain
- difficulty swallowing
- unexplained weight loss
- excessive sweating, particularly at night