Hi
I think you need them to separate their radiation volumes from surgery volumes,
it's not useful to get a combined #, they are entirely different procedures / the skills required are unrelated.
And then, if you want surgery, get multiple opinions on which surgical approach makes sense (translab, middle fossa, retrosig) and ask doctors how often they do the approach that makes sense for you, and can they provide statistics for facial issues, hearing preservation etc for each.
Some docs mostly do Translab, others do a lot of Middle fossa etc. so it matters which approach you need/want, and then make sure the doctor team has the most possible experience with that approach.
With 40% hearing, not sure if they will recommend one of the approaches that seeks to preserve hearing. Translab apparently has fewer risks but never preserves hearing. Larger tumors or more in CPA tend to require retrosig.
If you choose radiation, it sounds like you may be close to Pittsburgh, which is where Dr Lunsford is (UPMC), one of the very best for radio options.
At 1.5cm you have some time to sort it out, don't rush. but also you may request a repeat MRI sooner than 6 months. Some docs will suggest more like 3 or 4 month following the first diagnosis. If you have symptoms that were sort of abrupt, this may show more of a growth mode happening. But there is no sure bet on that.
Good luck - you are in the right place to become educated. You can join ANA and then get access to a library of really helpful webinars which are in members only section.