Definition

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

Alternative Names

Mesothelioma - malignant; Malignant pleura mesothelioma (MPM)

Causes

Long-term exposure to asbestos is the biggest risk factor. Asbestos is a fire-resistant material. It was once commonly found in insulation, ceiling and roofing vinyls, cement, and car brakes. Even though many asbestos workers smoked, experts do not believe smoking itself is a cause of this condition.

Older veterans make up 30% of the cases of mesothelioma due to exposure in the military ship, vehicle, and plane industry.

Men are affected more often than women. The average age at diagnosis is 60 years. Most people seem to develop the condition about 30 years after being in contact with the asbestos.

Symptoms

Symptoms may not appear until 20 to 40 years or longer after exposure to asbestos, and may include:

• Abdominal bloating
• Abdominal pain
• Chest pain, especially when taking a deep breath
• Cough
• Fatigue
• Shortness of breath
• Weight loss
• Fever and sweating

Exams and Tests

Your health care provider will do an exam and ask you the person about your symptoms and medical history. Tests that may be done include:

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

Mesothelioma is often hard to diagnose. Under the microscope, it can be hard to tell this disease apart from similar conditions and tumors.

Treatment

Malignant mesothelioma is a difficult cancer to treat.

There is usually no cure, unless the disease is found very early and the tumor can be completely removed with surgery. Most of the time, when the disease is diagnosed, it is too advanced for surgery. Chemotherapy or radiation may be used to reduce symptoms. Combining certain chemotherapy medicines may help decrease symptoms, but it will not cure the cancer.

Untreated, most people survive about 9 months.

Participating in a clinical trial (test of new treatments), may give the person 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.

Outlook (Prognosis)

The survival time varies greatly from several months to several years. The outlook depends on:

• The location of the mesothelioma
• The cell type of the mesothelioma
• The stage of the tumor
• The person's age and general health
• Whether surgery is an option
• The person's response to treatment

You and your family may want to start thinking about end-of-life planning, such as:

• Palliative care
• Hospice care
• Advance care directives
• Health care agents

Possible Complications

Complications of malignant mesothelioma may include:

• Side effects of chemotherapy or radiation
• Continued spread of cancer to other organs

When to Contact a Medical Professional

Make an appointment with your provider if you have symptoms of malignant mesothelioma.

Prevention

Avoid exposure to asbestos.

References

Baas P, Hassan R, Nowak AK, Rice D. Malignant mesothelioma. In: Pass HI, Ball D, Scagliotti GV, eds. IASLC Thoracic Oncology. 2nd ed. Philadelphia, PA: Elsevier; 2018:chap 53.

Davies HE, Sterman D, Gary Lee YC. Pleural malignancy. In: Broaddus VC, Ernst JD, King TE, et al, eds. Murray and Nadel's Textbook of Respiratory Medicine. 7th ed. Philadelphia, PA: Elsevier; 2022:chap 114.

McCool FD. Diseases of the diaphragm, chest wall, pleura, and mediastinum. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 86.

National Cancer Institute website. Malignant mesothelioma treatment (adult) (PDQ) -- Health professional version. www.cancer.gov/types/mesothelioma/hp/mesothelioma-treatment-pdq. Updated April 24, 2024. Accessed July 8, 2024.