[First experience of CyberKnife stereotactic radiotherapy for glomus jugulare tumors]

Glomus jugulare tumors (GJT) (AKA paraganglioma or chemodecroma) make 0.6% of head and neck tumors and 80% of jugular foramen lesions. Recently different types of stereotactic radiotherapy are actively used in their treatment. The given paper summarizes our first experience of using CyberKnife system in management of patients with paragangliomas. Since April 2009 till September 2011 34 patients with GJT were treated in department for radiation therapy of Burdenko Neurosurgical Institute using CyberKnife system. Mean age was 50.5 years (range 26-75 years). Mean volume of treated lesions was 14.6 +/- 10.96 cm3 (range--1.04-37.4 cm3). Stereotactic radiosurgery was performed in 4 patients. Mean prescribed dose was 17 +/- 3.1 Gy (13.7-22 Gy). 30 patients received hypofractionation treatment (3-7 fractions with total dose 18-35 Gy). Mean follow-up period in our series was 8 months (1-20 months). Control of tumor growth reached 100% because none of the patients needed any additional therapy (microsurgical resection or repeated radiotherapy). Persistent trigeminal neuropathy was observed in 1 case (5%). There were no constant impairment of VII, IX, X, XII and XIII cranial nerves in the series. Stabilization of auditory function was present in 9 (82%) of 11 patients with initially preserved hearing. Preservation of effective hearing was observed in 75% of patients. Stereotactic radiosurgery and hypofractionation using CyberKnife system are effective modalities in management of such complex neurosurgical disease as GJT. Neurological deterioration after radiation treatment is extremely rare and in most cases is transient.