Head and Neck Cancer: Radiation Therapy

Radiation kills cancer cells by focusing powerful X-rays at the tumor.

When radiation therapy is used

Your doctor may use radiation for any of these reasons:

• To shrink a large tumor before surgery

• To kill cancer cells that might be left in the area after surgery

• For tumors that can’t be removed with surgery

• If you can’t have surgery for other reasons

• For a tumor that grows back after surgery

• To help ease symptoms caused by advanced cancers 

Radiation to the head and neck area can cause problems with tissue healing after dental work. For this reason, your doctor may suggest you have a full dental exam before starting radiation. If you have dental problems, the doctor will want you to have an exam as soon as possible before radiation starts. Some or all of your teeth may need to be removed. This is because any dental problems you have can get worse with radiation.

How you get radiation

External beam radiation treatment (EBRT) is the type of radiation therapy most often used to treat head and neck cancer. The radiation comes from a large machine that focuses the radiation beams on the tumor. The machine doesn't touch you. Radiation treatment doesn't hurt. A mask or mold might be made to keep you in the same position for each treatment.

EBRT is done as an outpatient. That means you get it at a hospital or a clinic, but you go home the same day. Generally you have radiation treatments 5 days a week for several weeks in a row.

There are several types of EBRT. Some methods can target the tumor more precisely. This means they are less likely to damage nearby healthy tissue. These newer methods include:

• 3D-CRT (3D conformal radiation therapy). Computers and CT or MRI scans are used to match the radiation beams to the tumor’s shape from different angles. This means fewer side effects for healthy tissue.

• IMRT (Intensity-modulated radiation therapy). This is a similar method. It uses a computer to focus the radiation’s direction and strength more precisely on the tumor. This can also decrease side effects for healthy tissue.

Internal radiation is used far less often. With this method, radioactive materials are placed inside or near the tumor. The radiation travels a short distance for a certain amount of time to kill cancer cells. This type is given while you are in the hospital. The radiation is taken out before you go home. Some people get both this and EBRT.

Side effects

Radiation therapy affects normal cells as well as cancer cells. That means you may have side effects. What they are and how strong they are depends on:

• The amount of radiation

• If you are also getting chemotherapy

• What part of your body is being treated

Radiation to the neck and throat area can cause painful sores in your mouth and throat. These sores may make it hard to eat because it’s painful to chew and swallow. Sores often go away a few days to a few weeks after radiation ends. But to help you take in enough food, your doctor may insert a feeding tube into your stomach. This tube, called a PEG tube, is put in through a small cut or incision in your belly. The PEG tube will be taken out when it's no longer needed.

Other side effects from radiation therapy may include:

• Skin reddening or irritation

• Dry mouth or thick saliva

• Sore throat

• Hoarseness

• Swelling and scarring

• Appetite loss

• Trouble swallowing

• Decreased sense of taste

• Breathing problems caused by swelling

• Voice changes

• Ear aches or hearing loss

• Hair loss

• Tiredness

• Upset stomach or nausea

• Weight loss

Radiation side effects can be more severe when you have it along with chemotherapy. In rare cases, radiation may lead to a breakdown of cartilage in the voice box (larynx).

Radiation to the neck area might damage your thyroid gland. This can make you feel tired, gain weight, feel cold, and have dry skin or hair. If this happens, you might need to take thyroid hormone pills. 

Radiation near the salivary glands may cause dry mouth. You may have this even after treatment is done, because of lasting damage to your salivary glands. If you have dry mouth after radiation, be careful with your oral and dental health. Dry mouth can cause problems with tooth decay.

Talk with your doctor about what radiation side effects you might have and how these side effects might be prevented or managed.