CyberKnife stereotactic radiosurgery, stereotactic radiation therapy and stereotactic body radiation therapy: Technical and clinical updates

Since its clinical implementation in 1994, the CyberKnife radiosurgical system has transformed the field of stereotactic radiosurgery. Its frameless technology pioneered the role for hypofractionation, delivering radiation in a few high-dose sessions, as well as the application of stereotactic principles for extracranial treatments. Over the years, it has experienced considerable technological evolution, each enhancing imaging precision, treatment efficiency, and system usability. Hypofractionated stereotactic body radiotherapy treatments opened new treatment paradigms across a range of pathologies, including prostate cancer, lung cancer, pancreas cancer, liver malignancies, and cardiac arrhythmia. We describe the early development of the CyberKnife, highlight technologic updates to the system over time, review selected clinical treatment outcomes, and consider novel applications in the field of radiosurgery.