BACKGROUND: Peritumoral edema is a recognized complication following stereotactic radiosurgery (SRS).
OBJECTIVE: To evaluate the risk of posttreatment peritumoral edema following SRS for intracranial meningiomas and determine predictive factors.
METHODS: Between 2002 and 2008, 173 evaluable patients underwent CyberKnife or Gamma Knife SRS for meningiomas. Eighty-four patients (49%) had prior surgical resections, 13 patients had World Health Organization grade II (atypical) meningiomas, and 117 patients had a neurological deficit before SRS. Sixty-two tumors were in parasagittal, parafalcine, and convexity locations. The median tumor volume was 4.7 mL (range, 0.1-231.8 mL). The median prescribed dose and median prescribed biologically equivalent dose were 15 Gy (range, 9-40 Gy) and 67 Gy (range, 14-116 Gy), respectively. Ninety-seven patients were treated with single-fraction SRS, 74 received 2 to 5 fractions, and 2 received >5 fractions.
RESULTS: The median follow-up was 21.0 months. Thirteen patients (8%) developed symptomatic peritumoral edema, with a median onset time of 4.5 months (range, 0.2-9.5 months). The 3-, 6-, 12-, and 24-month actuarial symptomatic edema rates were 2.9%, 4.9%, 7.7%, and 8.5%, respectively. The crude tumor control rate was 94%. On univariate analysis, large tumor volume (P = .01) and single-fraction SRS (P = .04) were predictive for development of posttreatment edema.
CONCLUSION: SRS meningioma treatment demonstrated a low incidence of toxicity; however, large tumor volumes and single-fraction SRS treatment had an increased risk for posttreatment edema. Risk factors for edema should be considered in meningiomas treatment.
Published In/Presented At
Unger, K. R., Lominska, C. E., Chanyasulkit, J., Randolph-Jackson, P., White, R. L., Aulisi, E., Jacobson, J., Jean, W., & Gagnon, G. J. (2012). Risk factors for posttreatment edema in patients treated with stereotactic radiosurgery for meningiomas. Neurosurgery, 70(3), 639–645. https://doi.org/10.1227/NEU.0b013e3182351ae7
Medicine and Health Sciences
Department of Surgery