Stereotactic body radiotherapy (SBRT) is a minimally invasive treatment technique that allows for ultra-high doses of radiation to be delivered to small areas with precision not previously possible using older equipment. The CyberKnife® Robotic Radiosurgery System (Accuray, Sunnyvale California, USA) is a radiation unit specifically designed to focus beams of radiation accurately anywhere in the body. It is able to track, detect and correct for any tumor movement during treatment by using a sophisticated image guidance system.