Pathophysiology: Mesothelioma is a cancer which affects the membrane lining of the lungs and abdomen. It is most commonly caused by exposure to asbestos. The most common anatomical site for mesothelioma is the pleura (the outer lining of the lungs and internal chest wall), but it can also arise in the peritoneum (the lining of the abdominal cavity), the pericardium (the sac that surrounds the heart), or the tunica vaginalis (a sac that surrounds the testis). Once fibers cause biological damage, the stage is set for the decades-long latency period for the development of malignant mesothelioma.
Signs & Symptoms: Mesothelioma signs may not appear until 20 to 50 years (or more) after exposure to asbestos. The most common symptoms of peritoneal mesothelioma are abdominal swelling and pain due to ascites (a buildup of fluid in the abdominal cavity). Other features may include weight loss, fever, night sweats, poor appetite, vomiting, constipation, and umbilical hernia. If the cancer has spread beyond the mesothelium to other parts of the body, symptoms may include pain, trouble swallowing, or swelling of the neck or face.
Statistics: The most recent incidence statistics for mesothelioma are from 2010:515 Canadians were diagnosed with mesothelioma, 415 men were diagnosed with mesothelioma, 95 women were diagnosed with mesothelioma.The most recent mortality statistics for mesothelioma are from 2010:455 Canadians died from mesothelioma, 375 men died from mesothelioma, 85 women died from mesothelioma. Mesothelioma is less common among women (78 diagnoses in Canada in 2003, representing 18% of all new cases of mesothelioma diagnosed in that year), and the percentage of women with recognized occupational exposure is smaller.