Radiation therapy for malignant mesothelioma

Radiation therapy uses high-energy x-rays or particles to kill cancer cells. Mesotheliomas are often hard to treat with radiation therapy. They are not usually contained as single, discrete tumors, so aiming radiation at them while avoiding nearby normal tissues is difficult. But new radiation therapy techniques may make this form of treatment more useful.

Uses of radiation therapy

Radiation therapy may be used in different ways to treat mesothelioma:

• It can be used after surgery to try to kill any small areas of cancer that could not be seen and removed during surgery. This is called adjuvant radiation therapy.
• It can be used as a palliative procedure to ease symptoms of mesothelioma such as shortness of breath, pain, bleeding, and trouble swallowing.

Types of radiation therapy

Two main types of radiation therapy can be used to treat mesothelioma:

External beam radiation therapy (EBRT): This type of radiation therapy uses x-rays from a machine outside the patient’s body to kill cancer cells. It is the most common form of radiation therapy for mesothelioma. 

 

The treatment is much like getting an x-ray, but the radiation is more intense. The procedure itself is painless. Before your treatments start, the medical team will take careful measurements to find the correct angles for aiming the radiation beams and the proper dose of radiation. Each treatment lasts only a few minutes, although the setup time -- getting you into place for treatment -- usually takes longer. Most often, radiation treatments are given 5 days a week for several weeks.

With newer techniques, doctors can treat mesotheliomas more accurately while reducing the radiation reaching nearby healthy tissues such as the lungs. This may offer a better chance of increasing the success rate and reducing side effects.

For example, intensity-modulated radiation therapy (IMRT) is an advanced form of 3-dimensional radiation therapy. It uses a computer-driven machine that moves around the patient as it delivers radiation. It shapes the radiation beams to fit the tumor and aims them at the tumor from several angles, as well as adjusting the intensity (strength) of the beams to limit the dose reaching nearby normal tissues.

Brachytherapy: For this type of radiation therapy, a radiation source is placed inside the body, in or near the cancer. The radiation given off travels only a very short distance, which limits the possible damage to nearby healthy tissues. Brachytherapy is seldom used for this type of cancer.

Possible side effects

Side effects of external radiation therapy may include fatigue and sunburn-like skin problems and hair loss where the radiation enters the body. These usually go away once treatment is finished. Chest radiation therapy may cause lung damage and lead to trouble breathing and shortness of breath. Abdominal radiation therapy may cause nausea, vomiting, diarrhea, and a loss of appetite.

If radiation therapy is used together with chemotherapy, the side effects are often worse.

If you are having any side effects from radiation therapy, talk with your doctor. There are often ways to help control these symptoms.