Cyberknife Radiosurgery for Vestibular Schwannomas : Single-institution Experience

Lee, Gwang-Soo; Park, Hyung-Ki; Kim, Ra-Sun; Park, Sukh-Que; Cho, Sung-Jin; Chang, Jae-Chil

Original article

Journal of the Korean Society of Stereotactic and Functional Neurosurgery 2015;11(2):60-65.
Published online September 30, 2015.

Cyberknife Radiosurgery for Vestibular Schwannomas : Single-institution Experience

Gwang-Soo Lee, Hyung-Ki Park, Ra-Sun Kim, Sukh-Que Park, Sung-Jin Cho, Jae-Chil Chang

Department of Neurosurgery, College of Medicine, Soonchunhyang University, Seoul, Korea

Abstract

Background
It is less clear whether functional outcomes can be improved by fractionating the treatment over multiple sessions using Cyberknife (CK). In this study, we present our experience with multisession SRS using CK for VS by evaluating tumor control, hearing preservation, and complication rates.
Methods
48 patients were treated with CK SRS from 2008 to 2012 at Soonchunhyang University Hospital in Seoul. The data for 43 patients were retrospectively analyzed. Seventeen patients were treated in one session, and twenty four patients in 3 sessions. The median tumor volume was 1.4cc.
Results
With a median follow-up of 41 months (range, 13-65), no tumors required additional treatment. Radiographic tumor control rate was 93%. Of the 23 evaluable patients with pre-SRS serviceable hearing (Gardner-Robertson grade 1 and 2), the rate of serviceable hearing preservation was 87%. There were 3 cases of post-SRS facial weakness, but all cases were transient. Patients choose this modality because of its non-invasive nature and are generally very satisfied with their long term outcome.
Conclusion
CK SRS of VS were comparable to previously published series in tumor control and hearing preservation. However, multi-institutional, prospective studies are recommended to better evaluate SRS treatment outcomes.

Key Words: Acoustic neuroma, Vestibular schwannoma, Cyberknife, Hearing preservation, Fractionated, Radiosurgery.