Linac-based stereotactic body radiation therapy for treatment of glomus jugulare tumors

Background: Glomus jugulare tumors are rare, typically benign, tumors that arise from the neural crest cells that are associated with the autonomic ganglia in and around the jugular bulb. Treatment options for glomus jugulare tumors include embolization followed by resection, fractionated external beam radiation therapy (EBRT), stereotactic radiosurgery (SRS), and/or stereotactic body radiation therapy (SBRT). Materials and methods: 18 patients were treated with linear-accelerator based stereotactic body radiation therapy (SBRT) between May 2002 and November 2008. Fifteen patients (83%) had single glomus jugulare tumors and 3 patients had bilateral glomus jugulare tumors (although each of these patients had a single tumor targeted). The median tumor volume was 5.83 cm3 (range, 0.32–35.47 cm3). Ten tumors (56%) were previously untreated, and 8 (44%) tumors were persistent after previous surgical resection. One patient had undergone previous EBRT and 2 patients were previously treated with Gamma Knife radiosurgery to the intracranial portion of their tumor, with planned SBRT to the extracranial portion 2–4 months later at our institution. The median prescribed dose was 20 Gy in 3 fractions (range: 16–25 Gy in 1–5 fx) to the 80% isodose line. The median prescription coverage of the tumor was 93.6% (range: 83–98.72%). Results: Median follow-up for the entire cohort was 22 months. All the patients were alive at the time of the last follow-up with imaging available for review. The tumor was stable in 17 patients and decreased in size in one patient – yielding a local control rate of 100%. No patients experienced any new or worsening treatment-related neurologic deficits. Conclusions: SBRT is a safe and efficacious treatment modality for glomus jugulare tumors.