External radiation uses a machine called a linear accelerator (LINAC) to deliver radiation to the area of the oropharyngeal where the cancer cells are found. For oropharyngeal cancer, radiation treatment is typically delivered once per day (Monday through Friday) for 6-7 weeks. Some of the types of external radiation we use include:
- Intensity-modulated radiation therapy (IMRT)
With this method, 3D images from a computed tomography (CT) are used to create a treatment plan. The doctor identifies where the tumor is, and where it could spread, and selects radiation doses for each area. The doctor also identifies the healthy structures in the area that are to be protected from radiation, including the salivary glands, voicebox, inner ears, and spinal cord. A treatment plan is created so that beams come from angles all around a patient to provide dose to the targets and minimize dose to the normal tissues. This technique has been shown to provide excellent cure rates and minimize side effects. It is the most commonly used technique for oropharyngeal cancer treatments.
- 3D (3-dimensional) conformal radiation therapy (3D-CRT)
With this method, 3D images from the CT scan are used to create geometric fields that provide radiation dose to the tumor. Selected cancers in the oropharynx cancer are best served with this method, although most cases are treated with IMRT.
- Stereotactic body radiation therapy (SBRT) or stereotactic ablative radiation therapy (SABR)
This method is used selectively for patients with small areas of disease, typicaly for disease that has recurred after primary treatment. It uses 3D images to create a plan in which a high-dose of radiation is given in a very short amount of time, typically a few days).
Receiving radiation treatments
Radiation therapy does not cause pain at the time of treatment, so you won’t feel anything during your appointments. Radiation does not make you radioactive, and you can safely be around other people, including children.
The exact number and timing of your radiation treatments depends on the type of oropharyngeal cancer you have and the type of radiation therapy you need:
- Typically, you will be treated once a day, Monday through Friday, over 6-7 weeks.
- Most treatment sessions take 15 to 30 minutes, but some may take up to 1 hour.
- Once a week during your treatment, you will have a dedicated meeting with your radiation oncologist to discuss your treatment course, assess your progress, and provide counseling on preventing and treating any side effects.
Radiation therapy side effects
Everyone has a different response to radiation therapy. It may cause short-term side effects during treatment or long-term side effects after treatment ends.
The side effects of treatment depend on the type of radiation you receive, the dose, and your overall health. Common side effects that you may experience during radiation for oropharyngeal cancer include:
- Mouth and throat pain
- Mouth sores
- Changes in taste
- Thick saliva
- Difficulty swallowing
- Pain with swallowing
- Weight loss
- Poor appetite
- Redness, burning, and peeling of the skin in the treated area
- Hair loss of the beard area or posterior scalp
All attempts are made to limit long term side effects of radiation for head and neck cancer. However, some changes may persist after radiation treatment, including:
- Taste changes
- Decreased saliva
- Increased risk of jaw damage with trauma or dental extractions
- Difficulty swallowing
- Skin changes, with minor darkening or loss of beard in the treated area
- Jaw stiffness
- Risk of decreased thyroid hormone
- Fluid accumulation under the jaw (lymphedema)
No matter what you experience, your care team can help ease the side effects of treatment. At least once a week, your radiation oncology team will meet with you to discuss your progress and any side effects that you may have. After treatment, you will have regular follow-up visits with your treatment team.