Hi sandy,
When looking into radiation failures please keep in mind that surgery also has failures.
Both Cyberknife and gamma knife can be repeated once.
Also not all tumours are the same. Different gene defects mean that some AN's grow quickly and others do not. The fast growing bigger ones are the ones that typically create higher failure rates for both surgery and radiation.
At the moment your tumour is small, and if it is in the slow growing category, the chances of success with radiation are very high around 99% As the tumour size increases to 3.0cm, faster growth rates, the chances of success are definitely lower... Not sure of the numbers but I believe they are around 85%. There are genetic differences between AN's and the more aggressive ones are more difficult to treat with both microsurgery and radiation.
As for surgery after radiation. I believe the stats are one third are easier, one third is about the same and one third is more difficult, leading to facial palsy. So if you happen to be in that one third, the results are poorer, and overall that one third gives surgery after radiation poorer results than a first time surgery alone. Interestingly facial palsy after a second surgery is also high.
Please note that I am not a medical professional and these are my personal opinions.
Please do your own research.
Www.pubmed.com is a wonderful source of information to verify what I have written.
Any information you find on the internet should also be discussed with a medical professional, and with AN's you should speak with at least two experienced AN teams.