Radiation therapy for salivary gland cancer

Radiation therapy uses high-energy rays or particles to destroy cancer cells. Most people with salivary gland cancer have radiation therapy. Your healthcare team will consider your personal needs to plan the type and amount of radiation, and when and how it is given. You may also receive other treatments.

Radiation therapy is given for different reasons. You may have radiation therapy:

• after surgery to reduce the risk that the cancer will come back (recur) (called adjuvant therapy)
• as the main (primary) treatment for salivary gland cancer
• to relieve pain or control the symptoms of advanced salivary gland cancer (called palliative therapy)

Radiation therapy may be offered instead of surgery if surgery to remove the salivary gland tumour would cause a major change in your appearance or make it difficult for you to talk or eat. It may also be used as the main treatment if you aren't healthy enough to have surgery or if you don't want to have surgery.

You may also have radiation to the lymph nodes in your neck if you have:

• a high-grade, aggressive type of tumour that tends to spread to lymph nodes in the neck
• cancer that has spread to more than one lymph node
• cancer that has spread into tissues around the lymph nodes

Talk to your healthcare team to find out what you need to do before radiation therapy begins. They may discuss any or all of the following, depending on your personal needs.

Smoking during treatment may make radiation therapy for salivary gland cancer less effective. Smoking may also make side effects from radiation therapy worse.

If you smoke, your healthcare team will talk to you about how they can help you quit before starting radiation therapy.

It is important to have a complete dental exam before radiation therapy begins to prevent dental problems. Your dentist will determine if you need to have any dental work done before treatment can start, such as having unhealthy teeth removed. They will also develop a dental care plan for you to follow after radiation therapy.

Many people have a custom immobilization mask made before external radiation therapy is given to the head and neck. The mask makes sure that you don't move during treatment and that radiation is directed at exactly the same place each time. You will need to wear it during treatment planning and all radiation treatments.

During external radiation therapy, a machine directs radiation through the skin to the tumour and some of the tissue around it. It is the most common type of radiation therapy used for salivary gland cancer.

Conformal radiation therapy is a type of external radiation therapy that uses a special machine to direct the radiation beams to the shape of the area being treated. There are 2 main types of conformal radiation therapy used with salivary gland cancer.

Intensity-modulated radiation therapy (IMRT) delivers radiation beams at different intensities to different parts of the treatment area. A machine shapes the radiation beams very precisely, which can help spare the surrounding tissues from radiation. This type of radiation therapy is most often used for salivary gland cancer.

3-dimensional conformal radiation therapy (3D-CRT) shapes and aims the radiation beams from several different directions. All the beams are the same strength, or intensity. 3D-CRT is not used as often because IMRT is more precise at treating salivary gland tumours.

The schedule is the number of radiation therapy treatments and how often you have them. Radiation treatments for salivary gland cancer are usually done 5 days a week for 6 or 7 weeks. Your treatment may be shorter if you are having radiation therapy only to relieve symptoms like pain or bleeding.

Accelerated fractionation means giving the total dose of radiation over a shorter period of time by giving radiation more than once a day. This allows radiation treatments to be completed more quickly (for example, in 5 weeks instead of 7). Accelerated fractionation does not change the total radiation dose.

Side effects can happen with any type of treatment for salivary gland cancer, but everyone's experience is different. Some people have many side effects. Other people have few or none at all.

During radiation therapy, the healthcare team protects healthy cells in the treatment area as much as possible. But damage to healthy cells can happen and may cause side effects. If you develop side effects, they can happen any time during, immediately after or a few days or weeks after radiation therapy. Sometimes late side effects develop months or years after radiation therapy. Most side effects go away on their own or can be treated, but some side effects may last a long time or become permanent.

Side effects of radiation therapy will depend mainly on the size of the area being treated, the specific area or organs being treated, the total dose of radiation and the treatment schedule. Some common side effects of radiation therapy used for salivary gland cancer are:

• fatigue
• skin problems
• dry mouth
• swallowing problems
• taste changes
• trismus
• tooth decay
• earaches or difficulty hearing if the ear is in the treatment area
• osteoradionecrosis

Tell your healthcare team if you have these side effects or others you think might be from radiation therapy. The sooner you tell them of any problems, the sooner they can suggest ways to help you deal with them.

Find out more about radiation therapy and side effects of radiation therapy. To make the decisions that are right for you, ask your healthcare team questions about radiation therapy.