Malignant Mesothelioma: Radiation Therapy

What is radiation therapy?

Radiation therapy uses high-energy radiation from X-rays or particles to kill cancer cells.

When might radiation therapy be used?

Radiation can be part of the treatment for some mesotheliomas. Here are some reasons your healthcare provider may recommend this treatment:

• To try to kill any cancer cells left after surgery. When radiation is used after surgery, it’s called an adjuvant therapy. 

• To ease symptoms caused by tumors that can't be treated with surgery or that have spread to other organs.

To plan your treatment, you'll meet with a team of cancer specialists. This might include a surgeon, radiation oncologist, and medical oncologist.

What happens during radiation therapy

The most common way to receive radiation for this type of cancer is from a machine outside your body. This machine emits an invisible beam of X-rays or other particles. This is called external radiation. Sometimes special types of external radiation, such as intensity-modulated radiation therapy (IMRT), are used to try to limit the doses of radiation reaching nearby normal cells. Mesothelioma can be hard to treat with radiation because it often spreads along the lining of the lung (or another organ) without forming a distinct tumor. This can make it hard to aim the radiation without affecting nearby normal cells, such as those in the lungs.

A doctor who specializes in cancer and radiation is called a radiation oncologist. This doctor works with you to decide the kind of radiation you need. This doctor also determines the dose and how long you need the treatment.

Most people receive external radiation in an outpatient setting in a hospital or a clinic. This type of radiation is usually given for five days a week for several weeks.

Preparing for radiation

Before your first treatment, you’ll have an appointment. This is done to find exactly where on your body the radiation beam needs to be directed. The process is called simulation. It may take up to two hours. During this session, you may have imaging tests. These can include CT scans or MRI scans. These tests can help your healthcare providers know the exact spot of your tumor to better aim the radiation. Also at this session, you may have body molds made to help keep you from moving during the treatment. Then, you’ll lie still on a table while a therapist uses a machine to define your treatment field. The field is the exact area on your body where the radiation will be aimed. Sometimes it’s called your port. The therapist may mark your skin with tiny dots of semi-permanent ink. This is so the radiation will be aimed at the same place each time. 

On the days you get radiation

On the days you get treatment, you’ll lie on a table while the machine is placed over you. You may have to wear a hospital gown. It’s like getting an X-ray, only longer. It takes about 15 to 30 minutes to do. You should, though, plan on being there for about an hour.

At the start of the treatment session, a therapist may place blocks or special shields to protect parts of your body from exposure to radiation. The therapist then lines up the machine so that radiation is directed to the spot that was marked. When you’re ready, the therapist leaves the room and turns the machine on. You may hear whirring or clicking noises during radiation. This may sound like a vacuum cleaner. During the session, you’ll be able to talk to the therapist over an intercom. You can’t feel radiation, so the process will be painless. Also, you will not be radioactive afterward.

What to expect after radiation therapy

Because radiation affects normal cells as well as cancer cells, you may have some side effects. The side effects from radiation are normally limited to the area being treated. Some people have few or no side effects. If you do have them, your healthcare provider may change the dose of your radiation or the how often you receive treatment. Or he or she may stop your treatment until your side effects clear up. Tell your healthcare provider about any side effects you have.

Common side effects can include:

• Skin irritation or changes in areas on your skin that get radiation

• Fatigue

• Trouble breathing (from radiation to the chest)

• Nausea, vomiting, diarrhea, or loss of appetite (from radiation to the abdomen)

If you have any of these side effects, talk with your healthcare provider about how to deal with them. You should also ask what to do if your side effects become serious. Most of these side effects tend to go away a few weeks after you stop treatment.