Malignant Pleural Mesothelioma - Scientific Facts
Malignant pleural mesothelioma is not what you wanted the doctor to say. Initially, patients will have a hundred questions. This form of mesothelioma usually presents in the form of a tumor. It is the most common mesothelioma diagnosis with 90% of the mesothelioma patients testing positive. Most victims are finally tested for this disease when they show the mesothelioma symptom ofdyspnoea, a pain in the chest wall caused by pleural effusion. Devastatingly, this diagnosis is made when the disease is in an advanced stage. Without treatment, statistically patients only survive less than one year.
Historically linked since before the 1900’s, mesothelioma and asbestos exposure have an established relationship. Activities involving exposure before the industrial revolution are rarely documented but known. Widespread commercial production only happened after its thermal and fire retardant natural characteristics became apparent. Actually linking both asbestos and mesothelioma was not clearly documented until 1960 when Wagner described crocidolite exposure to asbestos in 33 cases in the north Western Cape of South Africa. This study was confirmed with eight controlled case studies that occurred between 1965 and 1975.
There are six types of asbestos that may be divided into two forms, serpentine and amphibole. Chrysotile is the only form of serpentine and is known as white asbestos, consists of curled fibers and it is this form that accounts for 95% of the asbestos used around the world. The amphibole group consists ofcrocidolite,amosite, anthophylliteandtremolite. These forms of asbestos are straight, needle-like, fibers and are easy to distinguish. Amosite is brown asbestos while crocidolite is blue asbestos and was used the most in industrial settings. There have been many studies of the epidemiology that yields conflicting reports associated with malignant pleural mesothelioma and the potential of chrysotile. Regardless of the type of asbestos, the World Health Organization (WHO) has concluded that all categories of asbestos cause mesothelioma cancer in humans.
Peritoneal mesothelioma has shown a significantly short period of latency. Malignant pleural mesothelioma may not be diagnosed for up to and longer than 30 years after asbestos exposure. There are studies that show an average latency period of about 42 years for some cases diagnosed between 1972 and 2004. In a study conducted in Italy, a latency period of almost 45 years was discovered in cases of malignant pleural mesothelioma that were diagnosed between 1993 and 2001. Many studies have demonstrated that there is an inverse relationship between mesothelioma and the duration of exposure to asbestos. That is, there has been a proven link between occupational exposure and degree of illness and latency period with non-occupational exposure victims. This dose dependence – where the degree of the illness is directly related to how long the victim was directly exposed.