Malignant Pleural Mesothelioma
Pleural mesothelioma is a cancer of the cells that make up the pleura or lining around the outside of the lungs and inside of the ribs. Its only known cause in the U.S. is previous exposure to asbestos fibers, including chrysotile, amosite or crocidolite. This exposure is likely to have happened twenty or more years before the disease becomes evident, since it takes many years for the disease to "incubate." It is the most common type of mesothelioma, accounting for about 75% of all cases.
Pleural mesothelioma is usually of two kinds:
(1) diffuse and malignant (cancerous), &
(2) localized and benign (non-cancerous.)
Benign mesotheliomas can often be removed surgically, are generally not life-threatening, and are not usually related to asbestos exposure. Malignant mesotheliomas, however, are very serious. Fortunately, they are rare – about two thousand people are diagnosed with mesothelioma in the U.S. each year.
Pleural Mesothelioma Symptoms
The early symptoms of mesothelioma are generally non-specific, and may lead to a delay in diagnosis. Sometimes resembling viral pneumonia, pleural mesothelioma patients may present with shortness of breath, chest pain and/or persistent cough; some patients show no symptoms at all. The onset of pleural mesothelioma is usually very slow, the most common presenting symptom is persistent pain localized in the chest. Sometimes the pain is accompanied by severe difficulty breathing, due to an accumulation of fluid in the pleural space known as pleural effusion. Cough, weight loss and fever are not uncommon. The most valuable single test to show the extent of the disease is a computed chest tomograph (CT-scan). A chest x-ray may show a build-up of fluid or pleural effusion. The right lung is affected 60% of the time, with involvement of both lungs being seen in approximately 5% of patients at the time of diagnosis. Less common symptoms of pleural mesothelioma include fever, night sweats and weight loss. Symptoms of peritoneal mesothelioma may include pain or swelling in the abdomen due to a build-up of fluid, nausea, weight loss, bowel obstruction, anemia or swelling of the feet.
Pleural Mesothelioma – Survival Rates
The median survival is about 17 months from the beginning of symptoms. The 3-year survival is 10% the 5-year survival is approximately 5% (if 100 patients are diagnosed with mesothelioma at a specific point in time, that means that 10 patients will still be alive at the end of 3 years and 5 patients will only be alive at the end of 5 years).