Treating prostate cancer, Part V: Radiation therapy
Along with active surveillance and surgery, radiation therapy (also known as radiotherapy) is one of the major options for managing early prostate cancer, and it also has a well-established role in the treatment of more advanced disease. It has been hard enough for a man with early prostate cancer to choose among these alternatives, and the decision is getting even harder. That's because radiation therapy is changing; there are now several options to choose from, including advanced methods for delivering external beam therapy, new techniques for providing internal radioactive seed therapy, and evolving strategies for combined radiation and hormonal treatment.
All forms of radiation contain energy; it's what burns your skin after an ill-advised day at the beach. Radiation therapy delivers much more energy, enough to kill cells. Because cancer cells are growing faster than normal cells and are less able to repair radiation damage, radiation therapy can be used to treat many forms of cancer. The trick is to focus the radiation on the tumor as precisely as possible. In the case of prostate cancer, doctors can focus the energy of radiation from outside the body (external beam radiation therapy) or from the inside, by placing radioactive seeds within the prostate (brachytherapy).
External beam radiation therapy
External beam therapy has been used to treat prostate cancer since the 1950s, but it has improved greatly since the late 1980s.