Mesothelioma may cause no symptoms in some cases, whereas in others it may cause cough, chest pain, and breathing difficulty, especially if a pleural effusion (collection of fluid around the lung) develops.
A chest X-ray may show abnormal shadowing; the diagnosis can be confirmed by examination of a sample of fluid from an effusion or by pleural biopsy (removal of a sample of tissue for microscopic examination).
Surgical removal of a small tumor may result in a complete cure. Usually, however, the tumor is diagnosed only after it has spread over a large area of the pleura. In such cases, there is no effective treatment, although radiotherapy may help to alleviate symptoms.