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 overall incidence of pleural mesothelioma in Ireland was 1.1 cases per 100,000 in men and 0.15 in women per year. Male incidence rates were 31% higher in the most socio-economically deprived areas compared to the least deprived regions. However a greater and statistically significant difference was noted between patients living in urban or rural areas, urban dwellers having 49% higher incidence. This may reflect higher proportions of manual workers in construction and related fields in urban populations.