This guide is for patients who have been

• Diagnosed with head and neck cancer.
• Need radiation therapy to treat that cancer.

This guide is to help you decide which type of radiation therapy you should choose to treat your head and neck cancer.

What does the guide cover?

Radiation can either be delivered from a machine outside of your body (called “external-beam radiation therapy”) or can be placed inside your body (called “brachytherapy”).

This guide only covers external-beam radiation therapy.

This guide explains differences among four types of radiation therapy and possible side effects.

This guide does not cover other forms of treatment for your head and neck cancer that you may be getting or have received, such as chemotherapy or surgery. This guide does not cover treatments for brain cancer or thyroid cancer.

If you are not sure if this guide is right for you, ask your doctor, nurse, or other health care professional.

Where does the information come from?

The information in this guide comes from a review of many different studies on radiation therapy for head and neck cancer. It is not based on a single study but on many studies looked at together by a team of researchers, doctors, and other experts.

What is cancer of the head and neck?

Most types of head and neck cancer start in the cells lining the open cavities of the head and neck, such as the sinuses, nasal cavity, mouth, or throat. Other kinds of head and neck cancer can occur in the salivary glands. These glands produce the fluid, called “saliva” or spit, that keeps your mouth and throat moist. Cancer of the brain and thyroid is not classified as head and neck cancer.

According to the National Cancer Institute, head and neck cancer accounts for nearly 3 to 5 percent of all cancer in the United States. These types of cancer are more common in men and in people older than age 50. Around 47,560 men and women in this country develop head and neck cancer every year. Tobacco and alcohol use are common risk factors for this cancer.

How is head and neck cancer treated?

There are several ways that doctors can treat head and neck cancer, including:

• Surgery, where a part or all of the tumor or cancer cells are removed.
• Chemotherapy, where certain drugs are used to kill cancer cells.
• Radiation therapy, where waves of energy are sent to kill cancer cells in and around the tumor.

Often, these treatments are used together. This guide is only about radiation therapy.

What is radiation therapy?

What are the side effects of radiation therapy?

What are the differences between radiation systems?

There are four external-beam radiation systems that doctors can use to treat your cancer. The first three of these have been used successfully to treat head and neck cancer for a number of years.

• The oldest system is called Two-Dimensional Radiation Therapy or 2DRT. This system targets the tumor using a two-dimensional image, much like a picture or photograph. The beams can only be aimed at a few angles and do not change strength while they are being given. 2DRT is not used as often as the newer systems.
• A newer sytem is called Three-Dimensional Conformal Radiation Therapy or 3DCRT. This system uses three-dimensional images that let doctors better target the tumor. The images are made with a computed tomography (CT) or magnetic resonance imaging (MRI) machine. The beams can be aimed at more angles than 2DRT to limit the amount of radiation to the normal areas around the tumor.
• A more recent system is called Intensity-Modulated Radiation Therapyor IMRT. This system is similar to 3DCRT, but the doctor can adjust the amount of radiation you get from each beam. This is done to try to reduce injury to the healthy areas around the tumor.
• Another system uses a different kind of energy beam to treat your tumor. This system is called Proton-Beam Radiation Therapy or PBRT. There is very little information about how well this form of radiation therapy works, and it is not widely used.

Which type of radiation therapy is most effective for my cancer?

• Doctors do not know if one type of radiation therapy is more effective than others in stopping or slowing down the growth of your head and neck cancer.
• Doctors do not know if any one type of radiation therapy will control your cancer better or help you live longer.

Which type may have fewer side effects?

• There is some evidence that IMRT causes less damage to the glands that make your saliva (the fluid or spit in your mouth) when compared to 2DRT or 3DCRT. Early results from a recent study suggest that when patients were examined 1 year after treatment, those who were treated with IMRT experienced dry mouth (xerostomia) less often than those who were treated with 2DRT or 3DCRT.
• While doctors think that IMRT may help avoid damage to other normal organs in the head and neck—such as your eyes, brain, and other glands—they do not know this for sure.
• The skill and experience of your doctors in using each type of radiation therapy may be important. The current studies were conducted in centers associated with universities and medical schools. Doctors do not know if the results are different in other types of medical centers.
• Doctors do not know how the side effects of PBRT compare to the other three types of radiation therapy.

Making a decision