https://www.youtube.com/watch?v=jmiaBPf0TkY In this video from Macmillan Cancer Support, oncologist Dr. Vincent Khoo from the Royal Marsden Hospital in London, U.K., talks about using radiation therapy (or radiotherapy) to treat cancer. MORE: Six symptoms of chronic fatigue Dr. Khoo explains that radiation therapy uses high energy X-ray beams to target cancer cells and stop them from growing. Radiation therapy can be used as a potential cure or as a palliative therapy to provide pain relief in advanced cases of cancer. The X-ray beams impact the cancer cells' ability to divide, but will also affect nearby healthy tissue. To prevent excessive damage to healthy tissues, doctors have to shape the radiation field to match the shape of the tumor and to very precisely target where the beams will enter the body. Radiation therapy is often given in short doses five times a week over a period of between five and eight weeks. MORE: 10 common emotional responses to a cancer diagnosis Prostate Cancer News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or another qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.