Radiation therapy uses ionizing radiation energy to kill cancer cells and shrink tumors. Radiation therapy injures or destroys cells in the area being treated by damaging their genetic material. This makes it impossible for these cells to continue to grow and divide.
Although radiation damages both cancer cells and normal cells, most normal cells can recover from the effects of radiation and function properly. The goal of radiation therapy is to damage as many cancer cells as possible, while limiting harm to nearby healthy tissue.
There are several types of radiation and different ways to deliver the radiation. The two broad categories of radiation therapy are external radiation therapy and isotope or internal therapy.
The most common form of external beam radiation therapy used in our practice is X-ray. X-rays can penetrate into the body to treat deep-seated tumors. Radiation therapy may be used alone or in combination with other cancer treatments, such as chemotherapy or surgery. In some cases, you may require more than one type of radiation therapy.
Before actually beginning your radiation treatment, a CT body scan is done to help plan the details of your treatment sessions. This step is called simulation/treatment planning. The CT scan generates specifics about your body shape and tissue density, which affects how the radiation beam is focused on the area of concern. You should expect this appointment to last about two hours.
The information obtained from the CT scan is compiled in a computer-generated treatment plan and relayed to your care team, including your radiologist oncologist, for analysis. It is very important that you are in the exact same position for each session so that the correct amount of radiation is delivered to a precise area. This planning phase helps your oncology team calculate those positional factors.
During treatment, your therapist at our Oncology Center may use molds, masks, or other devices to make sure your alignment is correct and to help you lie still. Once the therapist is certain you are positioned correctly, he or she will leave the room and start your radiation therapy. Video cameras and an intercom in the treatment room allow two-way communication between you and your therapist at all times.
The actual radiation treatment only lasts a few minutes. Depending on the location of your cancer and the details determined during the planning stage, the treatment machine may rotate around you but will not touch you. There is no pain or discomfort associated with radiation therapy. It feels the same as having an X-ray taken.
Learn more at National Cancer Institute website.