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Radiation therapy
Source: Oropharyngeal Cancer Treatment (PDQ®)–Patient Version, National Cancer Institute.
Source updated: May 16, 2025 · Captured 2026-09-09.
Selected source text with whitespace normalised. This Triangle page is not an NCI PDQ summary. Independent clinical review is pending.
Context: Treatment Option Overview / The following types of treatment are used:
Radiation therapy uses high-energy x-rays or other types of radiation to kill cancer cells or keep them from growing by damaging their DNA. External radiation therapy uses a machine outside the body to send radiation toward the area of the body with cancer.
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Certain ways of giving radiation therapy can help keep radiation from damaging nearby healthy tissue. These types of radiation therapy include:
Intensity-modulated radiation therapy (IMRT): IMRT is a type of 3-dimensional (3-D) radiation therapy that uses a computer to make pictures of the size and shape of the tumor. Thin beams of radiation of different intensities (strengths) are aimed at the tumor from many angles.
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Stereotactic body radiation therapy: Stereotactic body radiation therapy is a type of external radiation therapy. Special equipment is used to place the person in the same position for each radiation treatment. Once a day for several days, a radiation machine aims a larger than usual dose of radiation directly at the tumor. By having the person in the same position for each treatment, there is less damage to nearby healthy tissue. This procedure is also called stereotactic external-beam radiation therapy and stereotaxic radiation therapy.
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In advanced oropharyngeal cancer, dividing the daily dose of radiation into smaller-dose treatments improves the way the tumor responds to treatment. This is called hyperfractionated radiation therapy.
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Radiation therapy may work better in people who have stopped smoking before beginning treatment.
If the thyroid or pituitary gland are part of the radiation treatment area, the person has an increased risk of hypothyroidism (too little thyroid hormone). A blood test to check the thyroid hormone level in the body should be done before and after treatment.
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Learn more about External Beam Radiation Therapy for Cancer and Radiation Therapy Side Effects.
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Preserved source evidence · Independent clinical review pending · Not medical advice