Radiation treatment, also known as radiotherapy or radiation, RT, RTx, or XRT for short, is one of the most common forms of cancer treatments prescribed. Radiation therapy is now used, along with immunotherapy, chemotherapy, surgery and hormone therapy to treat all forms of cancer such as breast cancer, prostate cancer, colorectal cancer and ovarian cancer.
Radiation is used as a curative therapy (meant to cure cancer), an adjuvant or neoadjuvant therapy (in addition to another type of treatment), and as a palliative therapy (meant to reduce symptoms, but not to cure). It is a local treatment, not a systemic treatment, meaning it affects only the areas to which it is applied.
X-rays, a type of radiation, were first used to treat cancer in 1896, but the field of radiation oncology now includes many different types of radiation therapy. Treatments can be broken down into two types: external radiation therapy and internal radiation therapy.
External Beam Therapy
External beam therapy, also called external radiation therapy, or EBRT for short, is a type of treatment where a large machine directs beams of photons, protons, or electrons at the cancer area. Most external beam therapy courses last only a few minutes and are done daily for 5 days.
3D Conformal Radiation Therapy (3D CRT) uses MRI, CT, and PET images to map out a three-dimensional view of the tumor area. A computer then plans out the paths of radiation beams that directly target the cancer from multiple directions.
Intensity-modulated radiation therapy (IMRT) is a form of 3D CRT, but it uses smaller beams in addition to the larger, and beams can change their strength (intensity) depending on the location.
Image-guided radiation therapy (IGRT) is a form of IMRT, but imaging is used throughout the treatment process. This improves accuracy and reduces the exposure of the surrounding tissue to radiation.
Tomotherapy is also a form of IMRT. It directs radiation beams while simultaneously taking spiral-shaped CT scans throughout the radiation process.
Mantle-field radiation therapy, rarely prescribed nowadays, is a treatment that uses external radiation beams to broadly target the lymph nodes in the upper torso in Hodgkin lymphoma (HL) patients. This type of large-scale chest radiation is a breast cancer risk factor as well as a risk factor for heart disease and thyroid conditions.
Involved field radiation therapy (IFRT) is a type of Hodgkin lymphoma treatment that aims external beams at the entire area (“field”) where the treated lymph nodes exist.
Involved site radiation therapy (ISRT) is now the preferred treatment method for Hodgkin lymphoma over IFRT since it only targets the lymph nodes and the surrounding areas (the “involved site”).
Total body irradiation is when radiation is delivered to the entire body. This might be prescribed for Hodgkin lymphoma patients who are receiving stem cell transplants.
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Proton therapy, also called proton beam therapy or proton beam radiation, uses a device called a cyclotron to deliver protons (not the traditional photons) to the cancer site. Proton radiation can be targeted stronger, deeper, and to a more precise depth, so is often used for more advanced cancers and is more expensive.
Stereotactic radiosurgery (SRS) is often used for cancers of the brain and central nervous system in situations where the tumors are small and have clear edges.
Stereotactic body radiation therapy (SBRT), also called stereotactic radiotherapy (SRT), is similar to SRS but is used for cancers outside of the brain and central nervous system.
Whole brain radiation therapy (WBRT), or whole brain radiotherapy, is radiation given to the entire (“whole”) brain. Patients who receive this type of therapy usually have cancer that has spread to the brain or multiple brain tumors that can’t be removed with surgery.
Internal Radiation Therapy
Less common than external beam therapy, internal radiation therapy is a treatment that uses radioactive material inserted into the body near the tumor or where the tumor was removed. There are usually less side effects than with external beam therapy because the radiation is so targeted. Internal radiation therapy works best for smaller tumors.
Brachytherapy uses radioactive wire, disc or seed implants. It is often used to treat prostate cancer, vaginal cancer, womb cancer and cervical cancer. Depending on the situation and type of cancer, the implants can be left in the body for several minutes, days, or indefinitely. Brachytherapy can be HDR (high dose rate) or LDR (low dose rate).
Radioactive iodine (radioiodine) therapy, also called RAI therapy, uses iodine-131, a radioactive liquid, to treat thyroid cancer. This treatment works because the thyroid collects nearly all the body’s iodine, protecting the rest of the body from the radioactive substance.
Radioactive phosphorus therapy works similarly to RAI therapy, but it uses phosphorus (P-32) to treat certain blood disorders, such as essential thrombocythaemia (ET) and polycythaemia vera (PV).
Radium-223 & Strontium-89 are two other radioactive isotopes used to treat cancer, specifically cancer that has spread to the bones.
Radioembolization is a type of cancer treatment that uses radioactive yttrium (Y-90) to treat cancer that has spread to the liver.
Do you have questions about your radiation treatment options or need help with insurance or payments? SHAREing & CAREing is here to support you. We are a local non-profit founded and run by survivors. Contact us for individual support, attend a monthly support group meeting or join our online Facebook group. We offer free patient navigation services, links to free and reduced cost medical care, transportation assistance, and educational prevention workshops offered to schools and the community.
- “News of Science,” Science, 1957
- “External Beam Radiation Therapy for Cancer,” National Cancer Institute
- “Radiation Therapy for Hodgkin Lymphoma,” American Cancer Society
- “High incidence of late effects found in Hodgkin’s lymphoma survivors, following recall for breast cancer screening,” British Journal of Cancer, 2006
- “What is Proton Therapy,” Memorial Sloan Kettering Cancer Institute
- “Is Proton Therapy Safer than Traditional Radiation?” National Cancer Institute
- “What is Internal Radiotherapy,” Cancer Research UK
- “Usefulness of radium-223 in patients with bone metastases,” Baylor University Medical Center Proceedings, 2017
- “Radioembolization,” National Cancer Institute