Nasal cavity and paranasal sinus cancer

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Side effects of radiation therapy for nasal cavity and paranasal sinus cancer

Side effects can happen with any type of treatment for nasal cavity and paranasal sinus 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. Damage to these healthy cells may cause side effects. Side effects 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
  • the treatment schedule
  • whether or not chemotherapy is given during the same time period as radiation therapy (called chemoradiation)

Side effects tend to be worse with chemoradiation.

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.


Fatigue is one of the most common side effects of radiation therapy. It may be caused by anemia, poor appetite or depression. It may also be related to toxic substances that are made when cancer cells break down and die.

Fatigue usually occurs during or after the second week of radiation therapy. You may develop more symptoms of fatigue, or they may become worse, over the course of treatment. Fatigue usually goes away gradually after treatment ends, but some people continue to feel tired for several weeks or months after radiation therapy.

Find out more about fatigue and anemia.

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Skin reactions

Skin reactions happen because external beam radiation therapy has to travel through the skin to reach the area being targeted for treatment. The skin in the treatment area may become red, dry or change colour (become darker or tanned looking).

Most skin reactions occur within the first 2 weeks of receiving radiation therapy. They usually go away a few weeks after treatment. Some skin changes, like skin darkening or scarring, can stay for a long time.

Find out more about skin problems.

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Problems with the nose and sinuses

Radiation therapy for nasal cavity and paranasal sinus cancer can cause inflammation of the nose and sinuses. You may feel like your nose is blocked or stuffy. The mucus in the nasal cavity and paranasal sinuses may also become thick and dry. Radiation therapy may also cause narrowing of the nasal passages or bands of scar tissue, called synechiae, to form.

Talk to your healthcare team if you have problems with your nose or sinuses. They may suggest rinsing the nose with salt water and using a cotton swab coated with petroleum jelly to gently widen the nasal passage. Some people may need surgery if scar tissue completely blocks the nasal passage.

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Mouth problems

A sore mouth (also called stomatitis or oral mucositis) can occur because radiation can cause inflammation of the mucous membranes lining the mouth, throat and esophagus. A sore mouth may occur if radiation therapy includes the mouth or if chemotherapy is given at the same time as radiation therapy. Painful mouth sores, ulcers in the mouth and mouth infections can also develop.

Radiation can damage the salivary glands so they don’t make as much saliva. The risk of damage to the salivary glands is lower if you have intensity-modulated radiation therapy (IMRT), a very targeted form of radiation therapy. If the salivary glands are damaged, it can lead to dry mouth, or xerostomia. It occurs within the first 2–3 weeks of treatment and can become worse over time. It can take months or years for the salivary glands to recover. In some cases, they may not recover completely and dry mouth can become a permanent problem.

Follow the radiation therapy team’s instructions for mouth care. They may prescribe artificial saliva and can suggest other ways to help you cope with a dry mouth. Thorough, regular mouth care can help prevent a sore mouth and reduce infection. The healthcare team will give instructions about how often to clean and rinse the mouth and what to use. Pain medicines or special oral solutions may be needed to relieve pain.

Find out more about sore mouth, dry mouth and mouth care during cancer treatment.

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Dry eyes

External beam radiation therapy can damage the lacrimal gland, which produces tears. This can lead to dry eyes. The radiation therapy team may use a shield to protect the lacrimal gland during radiation therapy and reduce this side effect.

Eye drops are used to moisten the eyes if dryness becomes a problem. Dry eyes can sometimes develop as a long-term side effect. If this happens, you may need to use these drops every day. In rare cases, dry eyes can cause permanent damage to the eyes, which can lead to change or loss of vision.

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Difficulty swallowing

Radiation to the head and neck can lead to a sore mouth, less saliva or pain from an inflamed throat (called pharyngitis) or esophagus (called esophagitis). All of these problems can make swallowing painful or cause difficulty swallowing.

Difficulty swallowing usually starts about 2 weeks after treatment begins. It usually goes away when treatment ends and the inflammation lessens.

Tell your radiation therapy team if you have difficult or painful swallowing that makes it hard for you to eat. They may offer suggestions or prescribe medicines to ease pain.

Find out more about difficulty swallowing.

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Vision changes

Radiation therapy to the nasal cavity and paranasal sinuses can damage the lens and the blood vessels of the eye and optic nerve. This damage can cause some loss of vision and, in rare cases, lead to blindness. Radiation can also cause dry eyes and cataracts, which is when the lens of the eye becomes cloudy.

Vision changes most often occur years after radiation therapy is finished. They are more likely to happen when high doses of radiation are given. Newer radiation therapy techniques, such as 3-D conformal radiation therapy (3-D CRT) and intensity-modulated radiation therapy (IMRT), help lower the radiation doses to nearby tissues like the eye. Vision changes are less likely to occur if you have these types of radiation therapy.

Tell your doctor if you have any change in vision and have regular eye exams to check for early signs of changes to the eye.

Learn more about vision changes.

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Poor wound healing

Radiation therapy can delay wound healing and increase the chance of other wound complications, such as infection. People who have had the floor of the eye socket (called the orbit) rebuilt using a free bone graft are especially at risk of poor wound healing.

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Loss of appetite

Loss of appetite may also be called anorexia. It can be caused by some side effects of radiation therapy to the head and neck, including:

  • difficulty swallowing
  • nausea and vomiting
  • fatigue
  • changes in taste or smell that make foods less appetizing

Loss of appetite can lead to weight loss and malnutrition. Maintaining good nutrition during and after radiation therapy is important to help you recover from treatment. Talk to your healthcare team or a registered dietitian about steps you can take to increase your appetite, which will help you eat more and maintain your nutrition. They may also recommend nutritional supplements.

Find out more about loss of appetite and taste changes.

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Nausea and vomiting

Nausea and vomiting are not common side effects of radiation therapy to the head and neck, but they can occur. They may happen after the first or second week of radiation therapy. These side effects can usually be managed with antinausea medicines and usually go away after treatment ends.

Find out more about nausea and vomiting.

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Hearing loss

Radiation therapy to the head can cause earwax to harden, irritate tissue and cause damage to the little bones inside the middle ear or the Eustachian tube (tube connecting the middle ear to the upper part of the throat that opens and closes to regulate air pressure). These changes can lead to hearing loss. Hearing loss can be temporary and go away a few months after radiation therapy is done. Sometimes hearing loss can be permanent.

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Somnolence syndrome

Somnolence syndrome is a group of symptoms, including:

  • dizziness
  • headaches
  • confusion
  • trouble concentrating
  • an overall lack of energy (called lethargy)

You will also feel very sleepy and will want to sleep a lot.

These symptoms can occur 4–12 weeks after radiation therapy is finished. They can last up to 8 weeks. Symptoms usually go away on their own.

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Damage to the thyroid gland

Radiation to the neck or upper chest may affect the thyroid so it doesn’t make enough thyroid hormone (called hypothyroidism). The signs and symptoms of hypothyroidism may include extreme fatigue, dry skin, hair loss and intolerance to cold.

Treatment for hypothyroidism is thyroid hormone replacement therapy. Thyroid hormone is taken as a pill every day for life.

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Osteoradionecrosis is a rare side effect of radiation therapy. It is a condition that causes death of bone when radiation damages the blood vessels that supply the bone. It can lead to infection, fractures or pain.

When osteoradionecrosis develops, it most often affects the lower jawbone, or mandible. It is most often a late effect that develops after radiation therapy ends, so people are at risk for developing osteoradionecrosis for years following radiation therapy.

Dry mouth, or xerostomia, can contribute to osteoradionecrosis of the jaw bones. Careful mouth and dental care can help prevent this problem. Most people have a dental checkup before radiation therapy begins, and any unhealthy teeth are removed. Daily fluoride rinses are often prescribed to help strengthen teeth.

Your healthcare team may prescribe antibiotics to help treat osteoradionecrosis. You may also need surgery to remove or repair diseased bone. Some people may be offered hyperbaric oxygen therapy. This involves breathing pure oxygen in a pressurized room. It is done in a special chamber where the pressure inside is increased above the normal pressure of the atmosphere. The higher pressure allows more oxygen to get into your blood, which can help heal damaged and infected tissues.

Find out more about osteoradionecrosis.

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Radiation therapy to the jaw can cause scarring of the muscles and joints involved in chewing. Scar tissue makes the jaw stiff and sometimes prevents the mouth from opening wide. This side effect is called trismus. It can occur a few days or weeks after radiation therapy is completed and scar tissue forms.

Trismus can interfere with oral hygiene, fluoride treatments and dental care. Jaw exercises, such as opening and closing the mouth, can help and should be done regularly during and after radiation therapy.

Find out more about trismus.

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Low pituitary gland hormones

Radiation therapy can damage the pituitary gland if it is in the treatment area. The pituitary gland controls the release of certain hormones. If it is damaged, you may have low levels of the following hormones:

  • sex hormones such as estrogen, progesterone or testosterone
  • growth hormones
  • thyroid hormones
  • adrenal gland hormones

Lower levels of these hormones can cause problems such as lowered metabolism and feeling tired.

Low pituitary gland hormones is usually a late effect of radiation therapy. Your healthcare team will check hormone levels as part of your follow-up care. They may prescribe medicines to replace certain hormones.

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Damage to the brain

In some cases, radiation therapy for nasal cavity and paranasal sinus cancer causes damage to the frontal lobe of the brain. The damage causes death of brain tissue, called necrosis. This can lead to muscle weakness on one side of the body and personality changes. If this happens, you may need surgery to remove the damaged part of the brain.

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