Reduced-dose fractionated stereotactic radiotherapy for acoustic neuromas: maintenance of tumor control with improved hearing preservation.
Publication/Presentation Date
9-1-2013
Abstract
BACKGROUND: Fractionated stereotactic radiotherapy (FSRT) is a noninvasive treatment for acoustic neuromas (ANs). Initial reports from our institution demonstrated that the reduction of treatment dose to 46.8 Gy resulted in improved preservation of functional hearing status.
OBJECTIVE: We now report the tumor control (TC), symptomatic outcome, and hearing preservation (HP) rate in patients treated with reduced-dose FSRT.
METHODS: We analyzed all patients with AN treated from 2002 to 2011. All patients received 46.8 Gy in 1.8-Gy fractions. Follow-up audiogram and magnetic resonance imaging were performed in ≤ 1-year intervals. TC and HP were calculated by the Kaplan-Meier method. Analysis of HP, defined as Gardner-Robertson value ≤ 2, was determined by audiometric data. Non-hearing-related symptoms were defined by Common Terminology Criteria for Adverse Events version 4.
RESULTS: In total, 154 patients were analyzed. At a median follow-up of 35 months (range, 4-108), TC was achieved in 96% of patients (n = 148/154) and at 3 and 5 years was 99% and 93%. Eighty-seven patients had serviceable hearing at the time of FSRT and evaluable audiometric follow-up. Overall HP was 67% and at 3 and 5 years was 66% and 54%. Pure tone average decreased by a median of 13 dB in all patients. Nineteen percent (n = 31) of patients experienced symptom improvement, and 8% (n = 13) had worsening of symptoms. Cranial nerve dysfunction occurred in 3.8% of patients (n = 6).
CONCLUSION: Reduced-dose FSRT to 46.8 Gy for AN achieves excellent functional HP rates and limited toxicity without compromising long-term TC. Based on these promising outcomes, further attempts at dose deescalation may be warranted.
Volume
73
Issue
3
First Page
489
Last Page
496
ISSN
1524-4040
Published In/Presented At
Champ, C. E., Shen, X., Shi, W., Mayekar, S. U., Chapman, K., Werner-Wasik, M., Farrell, C. J., Gunn, V., Downes, M. B., Liu, H., Evans, J. J., & Andrews, D. W. (2013). Reduced-dose fractionated stereotactic radiotherapy for acoustic neuromas: maintenance of tumor control with improved hearing preservation. Neurosurgery, 73(3), 489–496. https://doi.org/10.1227/NEU.0000000000000019
Disciplines
Medicine and Health Sciences
PubMedID
23756743
Department(s)
Department of Surgery
Document Type
Article