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Studies have shown that people who are treated at centers that treat a lot of head and neck cancers with radiation, tend to live longer. And because of the complicated types of surgeries, along with the need for coordination between cancer specialists to make a complete treatment plan, it’s very important to have treatment at cancer centers by radiation oncologists who have experience in treating these cancers.

Radiation therapy uses high-energy rays or particles to kill cancer cells. When treating nasal and paranasal sinus cancers, radiation might be used in many ways:

• As the main (primary) treatment for people with small nasal cavity tumors. It doesn't change the way people look as much as surgery does.

• As the main treatment for people who can't have surgery due to poor health or because the tumor is too advanced to remove with surgery.
• After surgery (adjuvant treatment), to try to kill any small areas of cancer that are not visible at the time of surgery that might be left behind. This the most common treatment for these tumors -- surgery then radiation (sometimes given with chemotherapy).
• Before surgery (neoadjuvant treatment) to try to shrink the tumor so it's easier to remove. It might be given along with chemo.
• To help ease problems caused by the cancer, like pain, bleeding, and trouble swallowing when cancer spreads to areas beyond the head and neck. This is called palliative or supportive treatment.
• To treat cancer that has come back after treatment (recurrence).
• To treat lymph nodes in the neck even if they don't appear to have cancer cells in them. But not all doctors agree on this.
• For advanced nasal cavity or paranasal sinus tumors, chemotherapy is given along with the radiation. This is called chemoradiation. It often works better than radiation alone, but it also has more side effects. (See Chemotherapy for Nasal Cavity and Paranasal Sinus Cancer for more details.)

Radiation to this part of your body can affect your teeth and gums.  Before starting radiation treatments you will be advised to see a dentist. A dentist can make sure your mouth is healthy before treatment. They might recommend that certain teeth be removed before you start radiation because this can increase your chance of infection during treatment. During and after treatment your dentist can help check for and treat any problems that may come up, such as infection or tooth and bone damage.

Quit smoking before nasal cavity and paranasal sinus cancer treatment

If you smoke, you should quit. Your cancer might not shrink as well if you smoke during radiation treatment, you might have more side effects, and your benefit from radiation treatment might be less (which can raise your risk of the cancer coming back).   Smoking after treatment can also increase the chance of getting another new cancer. Quitting smoking for good (before treatment starts, if possible) is the best way to improve your chances of survival. It is never too late to quit. For help, see How To Quit Using Tobacco.

What type of radiation therapy is used to treat nasal cavity or paranasal sinus cancer?

The types of radiation therapy that might be used to treat nasal cavity and paranasal sinus cancer are:

• External beam radiation therapy (EBRT)
• Brachytherapy (internal radiation)

External beam radiation therapy

The main type of radiation therapy used to treat nasal cavity and paranasal sinus cancer is external beam radiation therapy. External beam radiation therapy focuses a beam of radiation from a machine outside of the body onto the cancer.

These tumors are close to the eyes, brain, glands, nerves, and blood vessels. Before your treatments start, the radiation team will use a CT scan to take careful measurements to determine the correct angles for aiming the radiation beams and the proper dose of radiation. A flexible but sturdy head and neck mask made of plastic mesh might be made to hold your head, neck, and shoulders in the exact same position for each treatment. Some people might feel a bit confined while this mask is on and might need to ask for medicine to help them relax during the treatment. Sometimes, the mask can be adjusted so that it is not too constricting. Your radiation oncologist can discuss the options with you. You might also be fitted for a bite block that you hold in your mouth during treatment.

Standard external beam radiation therapy for nasal cavity and paranasal sinus cancers is given in daily fractions (doses) 5 days a week for about 6 to 7 weeks. Other schedules for radiation may be used, too.

• Hyperfractionation refers to a slightly lower radiation dose that is given more than once a day (for example, twice a day for 7 weeks). Hyperfractionation is a schedule that is used often to deliver radiation for these cancers.
• Accelerated fractionation refers to the standard radiation dose being given each day but over a shorter amount of time (5 to 6 weeks) instead of the usual 7 weeks. For example, radiation is given 6 days a week over 5 weeks instead of the standard 5 days a week for 7 weeks.

There are also more advanced EBRT techniques that help doctors focus the radiation more precisely:

• Three-dimensional conformal radiation therapy (3-D CRT): 3D-CRT uses the results of imaging tests and special computers to map the exact location of the tumor. Several radiation beams are then shaped and aimed at the tumor from different directions. Each beam alone is fairly weak, which makes it less likely to damage the normal tissues it passes through. But the beams all meet at the tumor to give a high dose of radiation there.
• Intensity modulated radiation therapy (IMRT): IMRT is an advanced form of 3D-CRT therapy. IMRT is the standard way to deliver external beam radiation for these cancers. It uses a computer-driven machine that actually moves around the patient as it delivers radiation. Along with shaping the beams and aiming them at the tumor from several angles, the intensity (strength) of the beams can be adjusted to limit the dose reaching the nearby normal tissues. This may let the doctor deliver a higher dose to the tumor with fewer side effects.

Proton beam radiation therapy

Proton beam radiation therapy focuses beams of protons instead of x-rays on the cancer. Unlike x-rays, which go through the patient and expose the body to radiation both before and after they hit the tumor, protons stop moving after traveling a certain distance. So the tissues behind the tumor are almost protected from radiation and even tissues in front of the tumor are exposed to less radiation than the tumor. This means that proton beam radiation can deliver radiation to the cancer while doing less damage to nearby normal tissues. Because there are so many critical structures close by, proton beam radiation can be used to treat certain tumors of the nasal cavity or paranasal sinuses. But more studies are needed with proton therapy to evaluate long-term side effects and to see if it is better than IMRT.

Right now, proton beam therapy is not widely available. The machines needed to make protons are very expensive, and they aren’t available in many centers in the United States. Proton beam radiation might not be covered by all insurance companies at this time.

Brachytherapy

Brachytherapy (also called internal radiation or interstitial radiation), is another way to deliver radiation. Radioactive material is put right into or near the cancer. The radiation travels only a very short distance, which limits its damage of nearby normal tissues. This method of internal radiation therapy may be used with EBRT to treat nasal cavity and paranasal sinus cancers, but this is not common. More research is needed to know if it helps and how to best use it.

What are the possible side effects of radiation therapy for nasal cavity or paranasal sinus cancers?

If you are going to get radiation therapy, it’s important to ask your doctor about the possible side effects so you know what to expect and can find ways to manage them.

Common side effects depend on where the radiation is aimed and can include:

• Skin problems in the area being treated, ranging from redness to blistering and peeling
• Nausea
• Loss of appetite
• Feeling tired or weak
• Trouble swallowing
• Hearing problems
• Dry eyes or dry mouth
• Hoarseness
• Change of taste
• Bone pain
• Bone damage
• Brain damage (this is rare)

Most of these side effects go away slowly when treatment is over but some side effects can be permanent. For example, if your eye is in the path of the radiation beam, it could change the way you see through that eye. Side effects of radiation tend to be worse if chemotherapy is given at the same time. Tell your doctor about any side effects you have because there are often ways to lessen them.

Mouth sores: People treated with radiation to the head, neck, and throat area can get painful sores in the mouth and throat that can make eating and drinking very hard. This can lead to weight loss and poor nutrition. Some people might need a feeding tube (called a gastrostomy or G-tube) during treatment to give them nutrition. The mouth sores heal with time after the radiation has stopped, but some people continue to have problems swallowing long after treatment ends.  Ask about swallowing exercises you can do to help keep those muscles working and increase your chance of eating normally after treatment.

Narrowing of the nasal cavity: Sometimes, radiation to the nasal cavity can cause the cavity to get smaller or cause the nasal cavity tissues to stick together. This might make it hard to breathe. Simple techniques like gently rotating a cotton swab covered with petroleum jelly in the nose or rinsing the inside of the cavity with salt water might help open the tightened area a little so breathing is not a problem.  

Dry mouth: Radiation aimed at the head and neck might damage the salivary (spit) glands, leading to dry mouth that doesn't get better with time. This can cause discomfort and problems swallowing. It can also lead to tooth decay and damage to the jaw bone. People treated with radiation to the neck and throat must pay close attention to their oral health and see their dentist regularly.

Hormone problems: If the pituitary or thyroid glands are exposed to radiation, they might be damaged. Your doctor will do blood tests to see how well these glands are working. You may need to take medicine if there are problems.

Lymphedema: Some people treated with radiation therapy might be at risk of developing lymphedema in the head and neck areas that were radiated. These areas can become swollen and firm. This can be worse if the person also had surgery. Sometimes medicines, physical therapy, or massage therapy might be helpful.

Damage to the carotid artery: Radiation to the neck area might increase a person’s risk of stroke many years after treatment. This might be because of health problems that were already present before radiation such as narrowing of the artery or an increase in plaques both of which can lower blood flow. People who smoke are also at risk. Because of this some doctors might schedule regular ultrasounds for you after treatment, to keep an eye on your arteries.