Treatment > Cerebral Edema · Radiation Related Pathology · Radiosurgery

Meeting Abstract

Gamma-knife radiosurgery for meningiomas: Predisposing factors for cerebral edema

T. D. Olds, C. T. Chung, S. S. Hahn, C. Hodge, R. Schelper

SUNY Upstate Univ, Syracuse, NY; SUNY Upstate Medical University, Syracuse, NY

Purpose. Identify causative or contributory factors for the development of cerebral edema following Gamma Knife Radiosurgery (GKS) for meningiomas.

Materials and Methods. We evaluated 80 patients with meningiomas treated with Gamma-Knife radiosurgery at the Central New York Gamma Knife Center between August, 1998 and September, 2001.
Median age was 65 years (range 29-92).
Fifty-three were female and 27 male.
Twenty-seven had prior surgical resection (8 gross total and 19 subtotal) and 9 prior radiotherapy.
Three patients developed steroid-refractory edema after GKS eventually necessitating surgery.
Clinical findings, treatment course, imaging alterations, and pathologic findings of these three patients were reviewed and compared to the remaining 77 cases.
Particular attention was given to location, size, rapidity of symptom onset, histopathologic analysis, and underlying disease conditions.
Median follow-up was 11 months (range 1-33).

Results. Forty-six (58%) of the patients had meningiomas that were non-skull based.
The median treatment volume was 5.1 cc (range 0.4-3.8).
The median maximum dose was 30 Gy.
Three patients developed steroid-refractory edema within 2 months following GKS and eventually were treated with surgical resection for symptom relief.
None of these patients had prior resection, external-beam radiation therapy or GKS.
The volumes treated were 5.9, 18.4, and 22 cc treated with 17, 13, and 11 Gy (x2), respectively.
Two of the patients developed symptoms within 4 weeks of completing GKS, the other within 8 weeks.
All were postmenopausal females and hypertensive.
Two had a history of diabetes (medicated) and one was diagnosed with hyperglycemia following long-term steroid use.
Only one patient exhibited focal Ki-67 positivity.

Conclusion. Severe cerebral edema necessitating surgical intervention is a potential complication of GKS.
We cannot confirm that skull-based location, association with venous sinuses, prior surgery or radiotherapy contributes to the development of cerebral edema.
Predisposing factors such as hypertension and hyperglycemia were identified as possible contributors and should be further evaluated.

© Copyright 2003 American Society of Clinical Oncology All rights reserved worldwide