I have been meaning to post a reply on this, reporting on some news from the Symposium.
Dr. Telian at U. of Michigan had results of middle fossa surgery combined with high resolution MRIs. These MRIs are more expensive, but allowed them to determine ahead of time whether patients were likely to retain hearing. I believe that with this pre-screening, they can get 90% hearing retention. So while the surgery itself may have evolved as far as it going to go, there are still developments to be made in diagnostic tools. Hopefully one day everyone can get a clearer picture of the likely outcome in their case, rather than just the national averages. I think this may turn out to apply to both radiation and surgical treatment.
On the drug front, both Dr. Welling and Dr. Slattery reported on drug treatment research. The research is primarily aimed at developing drugs to slow down or stop the growth of schwannoma tumors, including ANs and others, in people with NF2. There are some good signs, but there are lots of hurdles to clear before they can do clinical trials for FDA approval. They will also probably be very expensive, and only really suitable for NF2 patients with multiple tumors.
Nevertheless, as you are aware, one advantage of watch and wait is that if the waiting comes to an end, by that time technology may have better tools available to deal with your AN. There are definitely some efforts being made to continue making progress in AN treatment.