Malignant mesothelioma is a cancerous tumor of the lining of the lung and chest cavity (pleura) or lining of the abdomen (peritoneum). Malignant mesothelioma is a disease in which cells of the mesothelium, a protective sac that covers most of the body’s internal organs, become abnormal and divide without control or order. They can invade and damage nearby tissues and organs.
“Malignant” is often dropped when discussing malignant mesothelioma, as all forms of mesothelioma are now referred to as malignant. When mesothelioma was first being researched, non-cancerous or benign fibrous tumors were discovered in the pleura and the term benign-fibrous mesothelioma was used. The prognosis for benign-fibrous mesothelioma is full recovery, whereas malignant mesothelioma is a terminal disease with no known cure. Benign-fibrous mesothelioma is not associated with asbestos exposure.
The primary cause for contracting malignant mesothelioma is through exposure to airborne asbestos fibers. Mesothelioma victims inhaled or swallowed asbestos fibers which then became lodged in the body. Because asbestos fibers are essentially indestructible, the body’s immune system is powerless to break them down.
Mesothelioma is a rare disease in the general population, with between two thousand and three thousand new diagnoses every year, mesothelioma is not rare among workers, or their families, in certain trades and industries. Malignant mesothelioma affects men more often than women with the average age at diagnosis being 60 years. Symptoms of mesothelioma may not appear until 30-50 years after exposure to asbestos.
Those at the highest risk for developing malignant mesothelioma include workers handling or installing insulation, and roofers, electricians, and miners. Asbestos fibers are so toxic that industrial and trade workers’ families are also at risk for developing mesothelioma through particles that cling to the workers’ clothing, shoes, skin and hair. This type of “second-hand” exposure to asbestos is known as para-occupational exposure.