Radiation Therapy

What is radiation therapy?

Radiation therapy, or radiotherapy, uses focused, high-energy photon beams to destroy cancer cells. There are different types of radiation. Your providers will help determine the best type and number of treatments for your type of cancer. 

Radiation might be used to cure cancer. It might also be used to help control the disease by keeping the cancer from growing and spreading. Sometimes it's used to help keep the cancer from coming back later. It can shrink tumors to ease symptoms, too.

Radiation may be the only treatment needed for some people. But it's most often used as a part of a treatment plan and given with chemotherapy, surgery or other cancer treatments. 

What are the types of radiation therapy?

External beam radiation – Radiation is sent from a machine directed at the part of the body where cancer is present. Common types of external beam radiation include:

  • Intensity-modulated radiation therapy (IMRT) shapes the radiation beams to match the tumor.
  • Stereotactic body radiation therapy (SBRT) uses high doses of focused radiation given in fewer treatments. It is often used to treat early-stage lung cancer when surgery is not an option.
  • Proton therapy is a type of radiation that delivers a high dose of radiation directly to the tumor, sparing the healthy tissue and organs.

Internal beam radiation or brachytherapy – Radiation that is given from within the body using devices, called implants, that are placed directly into or near the cancer.

Other types of therapeutic radiation include:

  • Radiation and chemotherapy used together – Chemotherapy may help how well radiation works.
  • Intraoperative irradiation – This means radiation is used during surgery.
  • Radioimmunotherapy – This uses antibodies tagged with a cancer-killing substance. These tagged antibodies find tumor cells and bind with them. This brings the cancer medicine directly to the tumor tissue. 

Treatment Overview

How does radiation work?

Radiation therapy is given as external or internal radiation. The way you get it depends on the type of cancer, where it is in your body, your overall health and your preferences. Sometimes both types of radiation therapy are used.

Internal radiation (brachytherapy, implant radiation, or systemic radiation)
Less often, a source of radiation may be put right into your body. It might be radioactive seeds or tubes that are put right into or as close to the cancer as possible. Sometimes a radioactive medicine is swallowed or put into your blood through a vein.

Internal radiation can be used to give a higher dose of radiation over a shorter time. The radiation only travels a short distance, so it kills the cancer cells with little damage to nearby tissues.

External radiation (external beam radiation therapy or EBRT)
Most radiation treatments are delivered through a large X-ray type of machine that sends the radiation beams through your skin and right at the tumor. The beams are often aimed at the tumor from many different angles. 

External radiation is aimed as precisely at the tumor as possible. This is important to help keep nearby normal tissues from getting too much radiation. External beam radiation therapy often starts with an appointment called simulation. This is needed to find exactly where on your body the radiation beam needs to be directed. 

Benefits and Risks

What are the benefits of radiation therapy?

The treatment goal of radiation therapy is to target cancerous cells precisely. It helps preserve healthy cells by destroying or stopping the growth of cancer cells in only the area where the cancerous cells appear. 

It may be used to:

  • Cure cancer
  • Kill cancer cells that remain after surgery or chemotherapy
  • Shrink a tumor so it can be taken out with surgery
  • Control cancer for a period of time
  • Reduce symptoms of cancer, such as pain or bleeding
  • Treat cancer that has come back

What are the risks of radiation therapy?

Radiation therapy poses a small risk of causing future cancers to develop because of radiation exposure. Talk to your doctor about the benefits vs. risks of receiving radiation for your cancer.

Side Effects

What are the side effects of radiation therapy?

You may or may not experience side effects while undergoing radiation therapy. 

Radiation therapy side effects might include:

  • Blurred vision
  • Brain fog
  • Fatigue
  • Hair loss
  • Headache
  • Nausea
  • Skin changes
  • Vomiting

Management & Support

After radiation therapy, you’ll likely continue having imaging scans done to see the success of the treatment. 

Before, during and after undergoing treatment, you may wish to seek out oncology support services. 

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