Many people undergoing cancer treatment receive some form of radiation therapy to shrink and kill a tumor. A relatively new type of radiation therapy — called image-guided radiation therapy (IGRT) — utilizes high-tech imaging with extremely precise radiation beams, ensuring that radiation targets the tumor, sparing nearby healthy tissue. IGRT can be used to treat many types of cancer, including those that develop in the spine, lung, prostate, brain, bladder, esophagus, liver, and bone.