Mesothelioma is a tumor arising from the cells of the pleura. The pleura is a membrane that covers the surface of the lung and lines the pleural cavity. There are two pleural cavities in the chest, each around the lung. Mesothelioma may be benign but its malignant forms are most common.
Note: Mesothelioma outside the pleura rarely arises from the cells of pericardium (heart lining membrane of the heart) and cells of the peritoneum (lining of the abdominal cavity).
Benign mesothelioma does not have a clear cause, but malignant mesothelioma has a clear link with the exposure to asbestos. Inhaled asbestos fibers not only damage the lungs giving rise to a disease called asbestosis, but they can also cause development of a cancer process in pleural cells. It should be noted that the process of mesothelioma development is very long and the mesothelioma may occur just after several decades after the contact with the asbestos.
Symptoms occur because of the growth of mesothelioma, which irritates the pleura and nearby lung. The patient suffers from fatigue, shortness of breath and dry cough. There is often present a chest pain that worsens during inspiration (pleural type of pain). The symptoms are very similar to a pneumonia and pleurisy. The tumor cells may cause production of fluid into the pleural cavity causing the pleural effusion compressing the adjacent lung. Advanced forms of mesothelioma manifest with general symptoms of advanced cancers such weight loss, night sweats and loss of appetite.
The doctors should examine every patient with the above-mentioned symptoms. It is important to know about any contact with asbestos, especially at the workplace. Physical examination should include cautious listening to the patient’s breathing with a stethoscope as the irritation of pleura may be accompanied with a characteristic frictional sound. The most used imaging methods include the chest X-ray and computed tomography. If we find the pleural effusion, it is very important to puncture the affected pleural cavity by a needle and get a sample of the fluid for cytological examination to confirm the presence of mesothelioma cells. Alternatively, the pneumologists can use diagnostic thoracoscopic surgery when the doctors put a special optical instrument through a chest incision into the pleural cavity.
The most important way of prevention is to avoid contact with asbestos. This is not always easy, given that the asbestos is used in industry and relatively recently it has been widely used in the building industry as a fire-resistant material.
The treatment is (as usually) a combination of surgery, chemotherapy and-or irradiation. The particular therapeutic approach depends on the size of the tumor, its location and presence of metastases. Generally speaking, when the tumor is not found in time, it has a bad prognosis no matter the therapy.