Mesothelioma is a form of cancer that is almost always caused by previous exposure to asbestos.[1] In this disease, malignant cells develop in the mesothelium, a protective lining that covers most of the body's internal organs. Its most common site is the pleura (outer lining of the lungs and chest cavity), but it may also occur in the peritoneum (the lining of the abdominal cavity) or the pericardium (a sac that surrounds the heart).

Most people who develop mesothelioma have worked on jobs where they inhaled asbestos particles, or have been exposed to asbestos dust and fibre in other ways, such as by washing the clothes of a family member who worked with asbestos, or by home renovation using asbestos cement products. There is no association between mesothelioma and smoking.[2]

Signs And Symptoms

Symptoms of mesothelioma may not appear until 20 to 50 years after exposure to asbestos. Shortness of breath, cough, and pain in the chest due to an accumulation of fluid in the pleural space are often symptoms of pleural mesothelioma.

Symptoms of peritoneal mesothelioma include weight loss and cachexia, abdominal swelling and pain due to ascites (a buildup of fluid in the abdominal cavity). Other symptoms of peritoneal mesothelioma may include bowel obstruction, blood clotting abnormalities, anemia, and fever. 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.

These symptoms may be caused by mesothelioma or by other, less serious conditions.

Mesothelioma that affects the pleura can cause these signs and symptoms:

chest wall pain

pleural effusion, or fluid surrounding the lung

shortness of breath

wheezing, hoarseness, or cough

In severe cases, the person may have many tumor masses. The individual may develop a pneumothorax, or collapse of the lung. The disease may metastasize, or spread, to other parts of the body.

Tumors that affect the abdominal cavity often do not cause symptoms until they are at a late stage. Symptoms include:

abdominal pain

ascites, or an abnormal buildup of fluid in the abdomen

a mass in the abdomen

problems with bowel function

weight loss

In severe cases of the disease, the following signs and symptoms may be present:

blood clots in the veins, which may cause thrombophlebitis

disseminated intravascular coagulation, a disorder causing severe bleeding in many body organs

jaundice, or yellowing of the eyes and skin

low blood sugar level

pleural effusion

pulmonary emboli, or blood clots in the arteries of the lungs

severe ascites

A mesothelioma does not usually spread to the bone, brain, or adrenal glands. Pleural tumors are usually found only on one side of the lungs.