Health and Lifestyles

Prevention

To reduce your risk of malignant mesothelioma, you should avoid exposure to asbestos. Because there is no safe level of asbestos exposure, any asbestos exposure is too much. In your home, especially if it is an older home, have an expert check for areas of exposed asbestos-containing insulation or other areas of deteriorating asbestos. These areas must be removed or safely sealed off professionally. Workers who routinely deal with asbestos-containing materials should use approved measures to limit their exposure and to keep from bringing asbestos dust home on their clothing.

Malignant mesothelioma is difficult to treat. The cancer can spread easily to nearby organs. If the tumor has spread, it is nearly impossible to remove the entire tumor surgically. In addition, it has been difficult to test the effectiveness of different treatments because there are relatively few cases of malignant mesothelioma.

The primary treatment options for malignant mesothelioma are surgery, radiation therapy and chemotherapy.

Surgery
Before any surgery is considered for the treatment of malignant mesothelioma, your overall health has to be evaluated. Tests are done to make sure the cancer has not spread to distant sites and to evaluate how well your lungs and heart are functioning. Lung tests look for any signs of lung damage from tobacco or from other diseases, including asthma and chronic obstructive pulmonary disease (COPD). These tests determine how risky surgery would be, especially if a lung needs to be removed.

Surgery for malignant mesothelioma can be aimed at long-term control of the cancer (aggressive surgery) or relief of symptoms (palliative procedures).

• Aggressive surgery — A procedure called extrapleural pneumonectomy involves removal of the pleura, the lung, the diaphragm and the pericardium. The intent of this very aggressive, complicated surgery is to remove as much of the tumor as possible. Not all centers will do this procedure because it is so complex and because it carries a high risk of death within 30 days after surgery. This procedure typically is done only in younger patients who are in good overall health with stage I disease. Patients are evaluated carefully to determine their ability to tolerate the surgery.



• Palliative procedures — When malignant mesothelioma is advanced, palliative procedures can be done to relieve or control symptoms such as breathlessness, which are caused by fluid or by the tumor pressing on the lung or other organs. These procedures do not cure the disease.
  
  
  • A procedure called thoracentesis can be used to treat fluid collection (effusion) in pleural mesothelioma. A needle is inserted into the chest to drain the fluid, relieving breathlessness and pain. Talc may be injected into the pleural space to try to stop fluid from accumulating there. This procedure is called talc pleurodesis. Similar procedures are used to relieve fluid collection (ascites) in peritoneal mesothelioma (paracentesis).
  
  
  
  • A procedure called pleurectomy and decortication is the surgical removal of the pleura. This procedure can be done to reduce pain caused by the tumor or to prevent the fluid from accumulating. For peritoneal mesothelioma, surgery generally is aimed at relieving symptoms.

Radiation Therapy
Because of the location of malignant mesothelioma, it is extremely difficult to deliver high enough doses of radiation to kill the tumor without damaging the surrounding organs. Lower doses of radiation can help to shrink the tumor, but it is unclear whether this helps people to survive longer than if they were not treated.

Using radiation therapy after surgery has not been shown to improve survival. However, because surgery is very unlikely to remove the entire tumor, radiation commonly is done after surgery in the hopes of killing remaining tumor cells. In addition, radiation therapy can be used to relieve the symptoms of mesothelioma, including chest pain.

Chemotherapy
Chemotherapy is the use of medications to treat cancer. Chemotherapy cannot cure mesothelioma. Some chemotherapy drugs have a partial effect in some patients. Combination chemotherapy (using more than one drug at the same time) may be given in an attempt to improve the patient's response to the medications. Some combinations have shown promise, and some new medications are being tried.

Like radiation therapy, chemotherapy may be administered after surgery in an attempt to kill cancer cells that could not be removed.

Treatment by Stage
Stage I (localized) mesothelioma — If you want aggressive treatment and are fit enough to have surgery, some centers may do an extrapleural pneumonectomy. Another surgical option is pleurectomy and decortication, which is sometimes done to relieve some of the symptoms of mesothelioma. Both of these procedures may be followed by radiation therapy or chemotherapy. Less than 5% of people with malignant mesothelioma are candidates for aggressive surgery.

Stages II, III and IV (advanced) mesothelioma — Pleurectomy and decortication may be done to relieve symptoms in pleural mesothelioma. Other procedures such as thoracentesis may be done to drain fluid (pleural effusions) and prevent them from recurring. Radiation therapy and/or chemotherapy also may be administered for symptom relief.

Recurrent malignant mesothelioma — There is no standard treatment for recurrent mesothelioma. Generally, treatments are considered that were not used the first time the disease was treated.

Clinical Trials and Future Treatments
New treatments for malignant mesothelioma and possible preventive measures, such as a vaccine, are being evaluated in clinical trials, and the future holds some promise. Clinical trials are research studies that evaluate new treatments for safety and effectiveness. There are no guarantees that a new treatment will work, and there are some risks. However, a clinical trial is not started unless the researchers believe the treatment may have some value.

Here are some of the treatments for malignant mesothelioma that are being evaluated:

• Combination chemotherapy — Different combinations of chemotherapy drugs have been tried with mixed results.
• Intracavitary chemotherapy — Researchers are looking at putting chemotherapy drugs directly into the pleural or peritoneal space because of a possible advantage over traditional chemotherapy. Because the drug is placed directly into the cavity, much greater doses can be given to patients without causing severe side effects. Some studies have shown this therapy to control effusions and reduce tumor size.
• Brachytherapy (intracavitary radiation therapy) — In this treatment, a radioactive substance is placed directly into the pleural or peritoneal space.
• Multimodality therapy — Multimodality therapy is any combination of surgery, radiation therapy and chemotherapy.
• Gene therapy — In this approach, a virus that has been genetically altered is introduced into the tumor. The virus infects the cancerous cells and makes them vulnerable to anticancer drugs.
• Immunotherapy — Treatments that stimulate the body's immune system to fight cancer cells are called immunotherapy.