In this study, we evaluate outcomes of skull base meningiomas treated with radiosurgery as an adjunct to microsurgery or primary treatment.

     We reviewed a prospectively compiled database detailing outcomes of 255 patients with skull base meningiomas. Fifty four males and 201 females had a median age of 55 years.

     Upfront radiosurgery was used in 109 patients and 146 patients were treated following surgery.

     Patients had meningiomas centered over the cerebellopontine angle (17%), clivus (16%), and petroclival (11%), petrous (2%), and parasellar (54%) regions. Median follow-up was 6.5 years (2-18 years). At last follow-up, 220 patients (86%) displayed no change or decreased volume, and 35 (14%) increased. Progression free survival at 3, 5, and 10 years was 99%, 96%, and 79% respectively. In Cox multivariable analysis, covariates associated with tumor progression include age greater then 65 (HR=3.41, p=0.001) and decreasing marginal dose (HR=0.90, p=0.05). At last clinical follow-up, 230 patients (90%) demonstrated no change or improvement in neurological condition and 25 deteriorated (10%). In multivariate analysis, factors predictive of new or worsening symptoms were increasing follow-up (OR=1.01, p=0.015), tumor progression (OR=2.91, p<0.001), decreasing maximum dose (OR=0.90, p=0.007), and petrous or clival location versus parasellar, petroclival and cerebellopontine angle (OR=3.47, p=0.018).

     This is a retrospective study.

     Stereotactic radiosurgery offers a high rate of tumor control and neurological preservation in patients with skull base meningiomas.

     After radiosurgery, better outcomes were observed for those receiving an optimal radiosurgery dose and harboring tumors located in cerebellopontine angle, parasellar, or petroclival locations.