whole-brain radiotherapy
(hole-brayn RAY-dee-oh-THAYR-uh-pee)
A type of external radiation therapy used to treat patients who have cancer in the brain. It is often used to treat patients whose cancer has spread to the brain, or who have more than one tumor or tumors that cannot be removed by surgery. Radiation is given to the whole brain over a period of many weeks. Also called WBRT and whole-brain radiation therapy.