Mesothelioma (malignant)

Definition

Malignant mesothelioma is an uncommon cancerous tumor of the lining of the lung and chest cavity (pleura) or lining of the abdomen (peritoneum) that is typically due to long-term asbestos exposure.

Alternative Names

Malignant mesothelioma

Causes, incidence, and risk factors

Long-term exposure to asbestos -- a fire-resistant material -- is the biggest risk factor. Asbestos was once commonly found in insulation, ceiling and roofing vinyls, cement, and automotive brake materials. Although many asbestos workers smoked, experts do not believe smoking is a cause.

Malignant mesothelioma affects men more often than women. The average age at diagnosis is 60.

Cases of mesothelioma seem to be increasing worldwide.

Symptoms

Symptoms may not appear until 20 - 50 years or longer after exposure to asbestos, and may include:

• Abdominal bloating
• Abdominal pain
• Chest pain
• Cough
• Fatigue
• Shortness of breath
• Weight loss

Signs and tests

• Chest x-ray
• Cytology of pleural fluid
• Open lung biopsy
• Pleural biopsy
• Thoracic CT

Mesotheliomas are often hard to diagnose under the microscope. It can be hard to distinguish between this type of tumor and other conditions and tumors of the pleura. More than one specialist may be involved in examining the biopsy. It may take some time for the diagnosis to be made.

Treatment

There is no cure. Untreated, the average malignant mesothelioma patient survives 9 months. It is a difficult cancer to treat.

Often the disease is too advanced for surgery. Chemotherapy or radiation may be used to reduce symptoms. Combining certain chemotherapy drugs may help decrease symptoms and improve survival, but it will not cure the cancer.

Consider participating in a clinical trial (test of new treatments), which may give you more treatment options.

Pain relief, oxygen, and other supportive treatments may also help relieve symptoms.

Support Groups

You can ease the stress of illness by joining a support group where members share common experiences and problems.

See:

• Cancer - support group
• Lung disease - support group

Expectations (prognosis)

The average survival time varies from 4 - 18 months. However, your outlook depends on:

• The stage of the tumor
• Your age and general health
• Whether surgery is an option

Complications

The tumor can quickly spread to other organs.

Calling your health care provider

Call for an appointment with your health care provider if you have symptoms of malignant mesothelioma.

Prevention

Avoid exposure to asbestos.

References

West SSD, Lee YCG. Management of malignant pleural mesothelioma. Clinics in Chest Medicine. 2006;27:335-354.

Camacho LH, Mora-Bowen A, Munden R, Smythe WR, Ordoñez NG. Malignant mesothelioma: natural history, pathologic features and future therapies. Am J Med. 2007;120:e7-9.

Mason RJ, Murray J, VC Broaddus, Nadel J. Textbook of Respiratory Medicine. 3rd ed. Philadelphia, Pa: WB Saunders; 2005:1994-2002.

Grainger RC, Allison D, Adam, Dixon AK. Diagnostic Radiology: A Textbook of Medical Imaging. 4th ed. Orlando, Fl: Churchill Livingstone; 2001:339-341; 514-515.