Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells. It is a type of local therapy. In early stage prostate cancer, radiation therapy may be the primary treatment (instead of surgery). It also may be used after surgery to destroy any cancer cells that may remain in the area. In advanced stages, radiation therapy may help relieve pain.
Doctors use two types of radiation therapy to treat prostate cancer:
- External radiation: The radiation comes from a machine. Patients go to the hospital or clinic for their treatment, generally 5 days a week for several weeks. Some men with prostate cancer receive 3-dimensional conformal radiation therapy. This type of radiation therapy more closely targets the cancer and spares normal tissue.
- Internal radiation (implant radiation or brachytherapy): The radiation comes from radioactive material placed in seeds, needles, or thin plastic tubes put directly in the tissue. The patient stays in the hospital. The implants generally remain in place for several days. Usually they are removed before the patient goes home.
Some men with prostate cancer receive both kinds of radiation therapy.