Long Term Outcomes With Linear Accelerator Stereotactic Radiosurgery For Treatment Of Jugulotympanic Paragangliomas

Background Data supporting linear accelerator (linac) stereotactic radiosurgery (SRS) for jugulotympanic paragangliomas (JTPs) come from small series with minimal follow-up. Herein, we report a large series of JTPs with extended follow-up after frameless linac-based SRS. Methods JTPs treated with linac-based SRS from 2002 to 2019 with 1+ follow-up image were reviewed for treatment failure (radiographic or clinical progression, or persistent symptoms after SRS requiring intervention) and late toxicities (CTCAE v5.0). Results Forty JTPs were identified; 30 were treated with a multifraction regimen. Median clinical and radiographic follow-up was 79.7 (interquartile range [IQR] 31.7-156.9) and 54.4 months (IQR 17.9-105.1), respectively, with a median 4.5 follow-up scans (IQR 2-9). Seven-year progression-free survival (PFS) was 97.0% (95% confidence interval 91.1%-100.0%). PFS was similar between single- and multifraction regimens (log rankP= .99). Toxicity was seen in 7.7% (no grade III). Conclusions With extended clinical and radiographic follow-up, frameless linac-based SRS provides excellent local control with mild toxicity <8%.