What is mesothelioma? What is its primary cause?
Mesothelioma is cancer of mesothelial cells, and occurs primarily in the pleural mesothelia surrounding the lungs. The mesothelia are two-layer membranes that protect most of the internal organs. About 10% of cases occur in the abdominal peritoneum, and it is also found, but less often, in heart pericardium and testicular tunica vaginalis. Prognosis is generally poor. Without treatment, median survival is 4 to 12 months, and patients that receive maximal supportive care generally survive one to two years post-diagnosis. Malignant mesothelioma is strongly linked with asbestos exposure. Inhaled asbestos fibers may damage mesothelia directly by interacting with the mitotic spindle, causing irregular cell division. Mesothelioma cell pathology includes loss of genetic material, including tumor suppressor genes likely to contribute to oncogenesis.