Types of Radiation Therapy

There are two main types of radiation therapy: external beam radiation therapy and internal radiation therapy. Your radiation oncologist will talk with you about the type that is best for your situation and the reasons why.

External Beam Radiation Therapy

External beam radiation therapy refers to treatments in which the radiation is generated from a source outside your body, and the beams are then pointed precisely at your tumor. This is the most common type of radiation therapy for cancer.

External-beam radiation therapy includes:

• Three-dimensional conformal radiation therapy (3D-CRT)
• Intensity modulated radiation therapy (IMRT)
• Stereotactic radiosurgery (including gamma knife radiosurgery)
• Intraoperative radiation therapy (IORT)
• Total body irradiation
• Electron therapy
• Proton therapy

Seattle Cancer Care Alliance (SCCA) offers all of these forms of external beam radiation therapy, and will be able to offer proton therapy in 2013. (SCCA is building a proton therapy center, slated to open in 2013.) Read more about each form of external beam radiation therapy.

Internal Radiation Therapy

Internal radiation therapy refers to treatments in which a radioactive substance is placed inside your body so it can release radiation from within. Often the substance is a small implant. It could also be a pill that you take by mouth or a fluid you get intravenously, or by IV.

Internal radiation therapy includes:

• Brachytherapy
• IORT using brachytherapy
• Systemic radiation therapy

SCCA offers all of these. Read more about each form of internal radiation therapy.