Radiation Therapy for Laryngeal and Hypopharyngeal Cancers

Radiation therapy uses high-energy x-rays, gamma rays, or particles to kill cancer cells. It may be used in different situations for laryngeal and hypopharyngeal cancers.

  • It can be used as the main (primary) treatment for some early stage laryngeal and hypopharyngeal cancers. If the cancer is small, it can often be destroyed by radiation without surgery. This treatment can help to preserve better voice quality.
  • It can be used to treat some patients whose health is too poor for surgery.
  • It may be used after a cancer is removed with surgery, to try to kill any small areas of cancer that may remain and lower the chance the cancer will come back. This is called adjuvant treatment.
  • It can be used to ease symptoms of advanced laryngeal and hypopharyngeal cancer such as pain, bleeding, trouble swallowing, and problems caused when cancer spreads to the bones.

Often, chemotherapy is given along with the radiation. This combination, called chemoradiation, can be more effective than radiation alone, but it also has more side effects. (See Chemotherapy for laryngeal and hypopharyngeal cancer for more details.)

Types of radiation therapy

There are 2 main types of radiation therapy.

External beam radiation therapy

This is the most common type of radiation therapy to treat laryngeal and hypopharyngeal cancer. Radiation from a source outside the body is focused on the cancer.

Before your treatments start, the radiation team will take careful measurements to determine the correct angles for aiming the radiation beams and the proper dose of radiation. Radiation therapy is much like getting an x-ray, but the radiation is much stronger. The procedure itself is painless. Each treatment lasts only a few minutes, although the setup time – getting you into place for treatment – usually takes longer.

Smoking during radiation treatment is linked to worse outcomes, so you should stop smoking completely before starting treatment. Smoking also increases the risk of the cancer coming back after treatment as well as the risk of getting another cancer, so quitting smoking for good is the best effective strategy to improve survival.

Radiation therapy for laryngeal and hypopharyngeal cancer is usually given in daily fractions (doses), 5 days per week, for about 7 weeks. Other schedules for radiation doses have also been studied:

  • Hyperfractionation means giving the total radiation dose in a larger number of doses (2 smaller doses per day instead of 1 larger dose, for example).
  • Accelerated fractionation means that the radiation treatment is completed faster (6 weeks instead of 7 weeks, for instance).

Hyperfractionation and accelerated fractionation schedules may reduce the risk of laryngeal and hypopharyngeal cancer coming back in or near the place it started (called local recurrence) and may help some patients live longer. The drawback is that these schedules also tend to have more severe side effects.

Modern techniques help doctors focus the radiation more precisely.

Three-dimensional conformal radiation therapy (3D-CRT): 3D-CRT uses the results of imaging tests such as MRI and special computers to precisely map the 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 normal tissues, but the beams converge at the tumor to give a higher dose of radiation there.

Intensity modulated radiation therapy (IMRT): IMRT is an advanced form of 3D therapy. It uses a computer-driven machine that actually moves around the patient as it delivers radiation. In addition to 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 most sensitive nearby normal tissues. This may let the doctor deliver a higher dose to the tumor. This is the most common way radiation is given for laryngeal and hypopharyngeal cancer.


Internal radiation therapy, also known as brachytherapy, uses radioactive material placed directly into or near the cancer. Brachytherapy may be used alone or combined with external beam radiation therapy. It is rarely used to treat laryngeal and hypopharyngeal cancer.

Side effects of radiation therapy

Many people treated with radiation to the neck and throat area have painful sores in the mouth and throat that can make eating and drinking very hard. This can lead to weight loss and malnutrition. The sores heal with time after the radiation has stopped, but some people continue to have problems swallowing long after treatment ends.

Other side effects of radiation therapy may include:

  • Skin problems in the area being treated, ranging from redness to blistering and peeling
  • Dry mouth
  • Worsening of hoarseness
  • Trouble swallowing
  • Loss of taste
  • Possible breathing trouble from swelling of the larynx
  • Tiredness

Most of these side effects go away after a short while. 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 help.

Radiation can affect your teeth, which could worsen any existing dental problems. Depending on the radiation plan and the condition of your teeth, some or all of your teeth may need to be removed before starting treatment.

Radiation aimed at the head and neck might damage the salivary glands, leading to dry mouth that does not improve with time. In addition to discomfort and problems swallowing, a dry mouth can lead to tooth decay. People treated with radiation to the neck and throat must pay close attention to their oral health.

When radiation is used as the main treatment for cancer of the larynx, it could very rarely lead to breakdown of the cartilage in the throat. If this occurs, the patient may need to be treated with a tracheostomy or laryngectomy.

For more information about radiation therapy, see the Radiation Therapy section of our website, or A Guide to Radiation Therapy.

The American Cancer Society medical and editorial content team
Our team is made up of doctors and master’s-prepared nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Last Medical Review: April 8, 2014 Last Revised: August 8, 2016

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