Radiation therapy, or radiotherapy, is the use of various forms of radiation to safely and effectively treat cancer and other diseases. Radiation therapy works by damaging the genetic material within cancer cells and limiting their ability to reproduce. When these damaged cancer cells die, the body eliminates them naturally. Normal cells also are affected by radiation, but are able to repair themselves in a way that cancer cells cannot. Your radiation oncologist may recommend using radiation therapy in a number of different ways. Sometimes the goal is to cure the cancer; in other cases, the goal is to reduce the symptoms caused by growing tumors and to improve your quality of life. When radiation therapy is administered for this purpose, it is called palliative care. In this instance, radiation may be used to shrink tumors that are interfering with your quality of life, such as a lung tumor that is causing shortness of breath, or to relieve pain by reducing the size of a tumor.
Some patients are concerned that radiation therapy will cause another cancer. Radiation therapy has been used safely and effectively to treat diseases for more than 100 years. The risk of developing a second tumor because of radiation therapy is very low. For many people, radiation therapy can cure the cancer. This benefit far outweighs any small risk that the treatment could cause a later cancer. However, you should discuss the risks and benefits of all of your treatments with your treatment team.