Oh thank you so very much for your quick reply! I didn’t expect to see it because the original post was from so long ago 😊. I am so pleased to hear about the great long-term results for your friend with cyber knife radiation. I originally had my paraganglioma ( which was located in the left carotid body region and was intertwined with the Vegas nerve) surgically removed way back in 1993. Left vocal cord paralysis and trouble with left swallowing resulted from the surgery. I learned in December 2020 that it had grown back and was the reason why I was having symptoms. I had cyber knife Radiation at Phoenix CyberKnife and Radiation Oncology Center, June 2021. My MRI in August showed that it had not yet shrunk, but I clearly now have almost no pain on that side now, And I can sleep on that side, whereas I hadn’t been able to for a long time, and my sweating has greatly reduced. The radiology oncologist says that it could take up to two years for the tumor to shrink. I am a little disappointed to hear that. I am wondering if anyone else out there has anything To say about CyberKnife Radiation?