Radiation therapy uses high-energy rays or particles to kill cancer cells. External beam radiation therapy uses radiation delivered from outside the body that is focused on the cancer. This is the type of radiation therapy that has been tried as a treatment for bone cancer.
Most bone cancers are not easily killed by radiation, and high doses are needed. These high doses can damage healthy structures like nerves in the nearby area. This is why radiation therapy is not used as a major treatment for most types of bone tumors, (except for Ewing tumors, and these are discussed in a separate document). Often radiation is used to treat bone cancers that are unresectable (they cannot be completely removed by surgery). Radiation may also be used after surgery if cancer cells were present in the edges of the removed tissue. Another term for this is positive margins (this was discussed in the section about surgery). In this case, radiation may be given to kill any cancer that may have been left behind. If the cancer comes back after treatment, radiation can help control symptoms like pain and swelling.
Intensity-modulated radiation therapy
Intensity-modulated radiation therapy (IMRT) is an advanced form of external beam radiation therapy. With this technique, a computer matches the radiation beams to the shape of the tumor and can adjust the intensity (strength) of the beams. The radiation is delivered to the tumor from several directions to reduce the amount of radiation that goes through any one area of normal tissue. Altogether, this makes it possible to reduce radiation damage to normal tissues while increasing the radiation dose to the cancer.
Proton-beam radiation is a special form of radiation that uses protons instead of regular x-rays to kill cancer cells. Protons are positively charged particles that are found inside all atoms. They cause little damage to the tissues they pass through but are very good at killing cells at the end of their path. This allows a high dose of radiation to be given to the tumor without hurting the normal tissue around it. Proton-beam radiation therapy requires highly specialized equipment and is not available in all medical centers. This form of radiation is very helpful in treating skull base chondrosarcomas and chordomas.
Side effects of radiation therapy depend on what area of the body is being treated and how much radiation is used. Common side effects include:
- Fatigue (tiredness)
- Loss of appetite
- Skin changes in the area being treated, ranging from redness and hair loss to blistering and peeling
- Low blood counts
- Nausea, vomiting, and diarrhea (these are more common if radiation is given to the belly)
More information on radiation therapy can be found in the Radiation section of our website, or in our document Understanding Radiation Therapy: A Guide for Patients and Families.
Last Revised: 01/21/2016