Dear Kristen
I can hear the panic in your post and certainly understand it. If your friend is able to travel, I would strongly encourage her to look into cyberknife radiation. It is a kind of stereotactic radiation that is very focused. Look up the company Accuray on the internet and they can give you sites across the country. There is a support group on line and the link is
www.cyberknifesupport.org. There are neurosurgeons and radiation oncologists who can answer questions if you can provide them with accurate details. 23 cm would be impossible, that's almost 10 inches and I don't think it's right. Maybe you can get a copy of the report and post your question to the cyberknife doctors on line. I have had brain mets and found them to be very kind and helpful.