Pleural Mesothelioma
Pleural mesothelioma spreads within the chest cavity, sometimes involving the lung. Metastases can occur in any organ, including the brain, and are much more common than previously thought.
The onset of 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).
There are currently no serum markers available for the diagnosis of mesothelioma. The detection of elevated serum levels of hyaluronic acid may be useful in differentiating mesothelioma from other tumors, or to follow the effect of treatment.
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).
Peritoneal Mesothelioma
Peritoneal mesothelioma involves the abdominal cavity, infiltrating the liver, spleen or the bowel. As with pleural mesothelioma, pain is the most common presenting complaint. In addition, due to fluid accumulation in the abdominal cavity (ascites), the abdomen appears enlarged. The patients experience nausea, vomiting, swelling of their feet, fever and difficulty in moving their bowels.
The prognosis is poorer than for pleural mesothelioma with a median survival time of about 10 months from the onset of symptoms.
A Benign Form of Mesothelioma
A rare form of mesothelioma is the cystic mesothelioma of the peritoneum, a thin membrane of mesothelial cells enveloping many of the organs in the abdomen. Its prognosis is benign. Most patients are managed by surgical resection. However, a reported high incidence of cyst recurrence has led to the use of hormonal therapy in isolated cases in an attempt to control cyst size and relieve local symptoms. Its occurrence has been described primarily in young women. Even though a benign prognosis, the diagnosis presents difficulties, requiring extensive electron microscopy and immunohistochemical studies.
Rare Forms of Mesothelioma
Mesothelioma of the pericardium is a very seldom seen cardiac cancer. The mass is usually detected at a late stage by echocardiography, the prognosis is very poor, with or without therapy. Mesothelioma of the ovaries and the scrotum have also been reported in the literature. The management differs based on the stage of the disease, the prognosis is also very poor. The etiology of the few cases of mesothelioma described in children remains unclear and is not believed to be asbestos-related, the therapy and prognosis differ on an individual basis.
