I had a 3+ cm tumor that was severely compressing my brainstem. I also had severe hydrocephalus caused by the tumor. My situation was deemed to be an emergency, and I had 2 surgeries... one to implant a VP shunt, and one to remove the tumor, a retrosigmoid surgery done by the chief of neurosurgery at Cedars-Sinai who has been on the cover of Time Magazine -- Keith Black M.D.
Due to my age and the position of the tumor and the way it was compromising my brain stem, I was told that I had no choice but to have it removed surgically by an experienced neurosurgeon ASAP. They were also unsure whether the tumor was a menigioma or an AN, although my hearing was severely compromised in a short time and my balance and facial nerve were also affected. We decided on Dr. Black (it was only a few days before the shunt was implanted after diagnosis, and another week for the tumor resection).
Although I had significant problems during the after surgical recovery due to swelling and I did lose all of my hearing, my facial nerve is barely compromised. It is only noticeable to me, and if I had to quantify, I would say it has a 5 - 10% deficit, but in the 5+ years since the surgery, it has improved dramatically. Balance is really not an issue for me anymore, and I have just gotten a Transear which helps with the SSD, but honestly, I haven't found that to be a big deal. I am just glad that he was able to get the whole darn thing out. It was a long surgery, like 7 hours or so, and the resection was very delicate. I am sure that a lesser surgeon would have made a lot bigger mess. Nevertheless, I have almost no residual problems. No headaches. The mildest of facial palsies, and best of all, no more treatment -- I just have it scanned every so often.
Good luck.