Cyberknife radiotherapy for vestibular schwannoma

Stereotactic radiosurgery is a well-established treatment modality for vestibular schwannoma. Initial reports using single-stage radiosurgery have demonstrated excellent tumor control rates. Many patients now elect to undergo radiosurgery given the potential for tumor control while avoiding the morbidity associated with microsurgical resection. In attempt to improve hearing preservation rates of single-state radiosurgery, staged frame-based radiotherapy using a 12-hour interfraction interval was used at the authors' institution and has shown a hearing preservation rate of 77% at 2 years of follow-up. With the arrival of the Cyberknife, a frameless, image-guided radiotherapy system, staged stereotactic radiotherapy for vestibular schwannoma became more practical. This article outlines the rationale and treatment protocols developed at Stanford University (California) and reports the authors' initial experience using the Cyberknife to treat vestibular schwannoma.