OS12 - 137 The Geriatric Scoring System (GSS) for Risk Stratification in Meningioma Patients as a Predictor of Outcome in Patients Treated With Radiosurgery

Abstract

Meningiomas are the most common primary benign brain tumor. Radiosurgery (primary or adjuvant) allows excellent local control. The Geriatric scoring system (GSS) for pre-operative risk stratification and outcome prediction of patients with meningiomas has been previously reported. The GSS incorporates eight tumor and patient parameters on admission. A GSS score higher than 16 was previously reported to be associated with a more favorable outcome. We assessed the validity of the GSS score and its influence on outcome in patients treated with gamma-knife radiosurgery (GKRS). Methods: Patients treated with single session GKRS for WHO-1 meningioma during 1989-2013 at the University of Virginia were reviewed. A cohort of 323 patients, 50.2% (n=162) males. Median age was 56 (29-84), and median follow-up was 53.6 (6-235) months. Median tumor volume was 4.5 cm3 (0.2-23). Median margin and maximal doses were 15 Gy (8-36) and 32.3 Gy (20-65), respectively. Results: Tumor volume control was achieved in 87% (n=281), and post-GKRS clinical neurological improvement reported in 66.3% (n=214). The median change in KPS was +10 (range -30 to +40). The most common complication was intermittent headaches (34.1%, n=110) and cranial nerve deficits (14.2%, n=46). The GSS (calculated and grouped as GSS>16 and GSS<=16) was found to correlate with different Post-GKRS functional status (p<0.0001) and tumor control (p=0.028). Conclusion: The GSS, used for risk stratification and outcome prediction in patients with meningiomas seems valid for patients undergoing single session GRKS. GSS score greater than 16 is associated with a better long-term functional status and tumor control.