Stereotactic Radiosurgical Treatment of Glomus Jugulare Tumors.

Objective: Determine treatment outcomes of stereotactic radiosurgery (SRS) for glomus jugulare tumors (GJT), focusing on three-dimensional volume change and symptoms before and after SRS, as well as complications related to SRS. Study Design: Retrospective case review. Setting: Tertiary referral center. Patients: Thirty-eight patients treated with SRS between 2000 and 2015. Intervention: SRS treatment of GJT. Main Outcome Measures: The tumor volumes on pre- and posttreatment imaging were compared utilizing the Leskell GammaPlan treatment plan software to assess tumor progression. Pre- and posttreatment symptoms, Fisch classification, and complications were recorded. Results: The mean radiographic follow-up was 39.1 months. The mean dose-to-tumor margin was 13.2 Gy. The mean tumor size at treatment was 5.8 and 5.2cm(3) at last follow-up. Thirty-three patients had follow-up imaging suitable for analysis. When defining both 10 and 15% tumor size increases as significant, 27 (82%) and 29 (88%) tumors decreased in size or remained stable, respectively. For the seven tumors with documented pre-SRS growth, treatment success was 86%. The mean marginal dose for treatment success and failure were 13.2 and 13.7 Gy, respectively. Patients receiving a higher margin dose had a greater risk of tumor progression (p = 0.0277). Fisch classification did not impact tumor progression rate. Initial tumor volume had no significance on tumor response to SRS. Conclusions: SRS is an effective treatment option for GJT. Both initial tumor volume and Fisch classification did not impact tumor progression. There were no significant patient or lesion characteristics that distinguished treatment success and/or failure.