Mesothelioma (malignant)

Definition

Malignant mesothelioma is a cancerous tumor of the pleura (lining of the lung and chest cavity) or peritoneum (lining of the abdomen) that is almost always caused by sustained exposure to asbestos.

Causes

Malignant mesothelioma is a diffuse tumor that affects men more frequently than women. Sustained exposure to asbestos is the biggest risk factor. It can take 20 to 50 years or even longer between exposure to asbestos and onset of the disease.

The median age of diagnosis is 60. The tumor can spread rapidly to involve the pericardium (sac around the heart), mediastinum, and the other pleura. Worsening pain and shortness of breath can occur. The tumor is usually associated with a pleural effusion

It can be hard to distinguish between this type of tumor and other conditions and tumors of the pleura, even when experienced pathologists are viewing biopsy samples.

Symptoms

• Shortness of breath
• Chest pain
• Cough
• Weight loss

Exams and Tests

• Chest x-ray showing tumor and possibly showing pleural effusion (which may be bloody)
• Thoracic CT
• Cytology from pleural fluid
• Open lung biopsy

Treatment

Results of treatment for malignant mesothelioma have been disappointing. When found early, surgery may cure it. Having chemotherapy and radiation before the surgery may help increase the chance of being cured.

When the disease is too advanced for surgery, chemotherapy or radiation may be used to reduce symptoms, but being cured is usually not possible.

A 2002 study showed that a chemotherapy regimen of two drugs -- cisplatin and pemetrexed -- appears promising in improving survival and decreasing symptoms. Other new chemotherapy drugs and combinations of drugs are gradually improving the treatment of malignant mesothelioma. Consider participating in a clinical trial (test of new treatments), which may give you additional treatment options.

Supportive treatment (such as pain relief and oxygen) may also help to relieve symptoms.

Support Groups

The stress of illness can often be helped by joining a support group where members share common experiences and problems. See cancer - support group and lung disease - support group.

Outlook (Prognosis)

The median survival time varies from 4 to 18 months in different studies. However, prognosis depends on the stage of the tumor and whether surgical removal of the tumor is an option.

Possible Complications

Rapid spread of the tumor to other organs is a complication.

When to Contact a Medical Professional

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

Prevention

Avoid exposure to asbestos.

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.