What is radiation therapy? "Radiation" is a treatment which aims beams of special energy at the tumor. It is used to help get rid of tumor cells. Radiation shrinks the tiny parts of a tumor that the surgeon cannot see or cannot operate on. Radiation is done as an "outpatient," meaning you go to the hospital for just a short time each day that your radiation treatment is scheduled. Some brain tumors need radiation therapy, some do not. Your doctor will decide if radiation is the right treatment for your tumor. If you have any questions about going through radiation treatment, don't be afraid to ask your doctors and nurses. Answered by Deneen Hesser, nurse educator, American Brain Tumor Association July, 2007