What you can expect
By Mayo Clinic staffExternal beam radiation for prostate cancer is conducted using a linear accelerator — a machine that directs high-energy beams of radiation into your body. As you lie on a table, the linear accelerator moves around you to deliver radiation from many angles. The linear accelerator delivers the precise dose of radiation planned by your treatment team.
External beam radiation therapy is typically:
- Given on an outpatient basis
- Administered five days a week over a period of about seven to nine weeks
Each treatment session usually lasts less than an hour. Most of that is preparation time. The actual radiation treatment only takes a few minutes.
During a treatment session:
- You lie down in the position determined during your radiation simulation session.
- You might be positioned with customized immobilization devices to hold you in the same position for each therapy session.
- The linear accelerator machine may rotate around your body to deliver radiation beams from different directions.
- You lie still and breathe normally during the treatment.
- Your radiation therapy team stays nearby in a room with video and audio connections so that you can talk to each other.
- You shouldn't feel any pain. Speak up if you feel uncomfortable.
- External beam therapy (EBT). Radiological Society of North America. http://www.radiologyinfo.org/en/info.cfm?pg=ebt. Accessed March 4, 2013.
- DiBiase SJ, et al. External beam radiation therapy for localized prostate cancer. http://www.uptodate.com/home/. Accessed March 5, 2013.
- Cozzarini C. Low-dose-rate brachytherapy, radical prostatectomy, or external-beam radiation therapy for localised prostate carcinoma: The growing dilemma. European Urology. 2011;60:894.
- Prostate cancer. American Cancer Society. http://www.cancer.org/cancer/prostatecancer/detailedguide/index. Accessed March 4, 2013.
- Tanagho EA, et al. Smith's General Urology. 17th ed. New York, N.Y.: The McGraw-Hill Companies; 2008. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=21. Accessed March 5, 2013.
- Radiation therapy. Prostate Cancer Foundation. http://www.pcf.org/site/c.leJRIROrEpH/b.5813857/k.AACD/Radiation_Therapy. htm. Accessed Dec. 8, 2010.
- Wong WW (expert opinion). Mayo Clinic, Rochester, Minn. March 6, 2013.


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