Hi, Jpark, good to virtually meet you. And, I'm sorry to welcome you to the AN club. I know how spooky and stressful this journey is, especially in the beginning, and I regret that you are going through that.
The good news, though, is twofold:
1. The folks here are super supportive and helpful, and there is a ton of very helpful information to be found here.
2. Having an AN really stinks and can be super scary at first, but you can rest assured that it's going to be OK.
I think regarding your course of treatment everything depends on your tumor's specific details, your medical history, etc. I'm not a medical doctor so I am not qualified to suggest anything specific about your case, but if you are comfortable sharing a bit more information about your situation perhaps someone who has been through a similar sort of AN can chime in with their experience. Do understand, though, that everyone's journey is different.
In my personal case, I have a very rare location for my AN which renders it entirely untreatable without destroying my natural hearing. So, "wait and watch" is the only course of action for me. As you might imagine, I found that "plan" unhelpful so I collected a LOT of second opinions from a bunch of different doctors. I personally think that approach makes a lot of sense for you here: I would strongly suggest you talk to multiple people who have experience specifically with treating ANs. You don't have to talk to 10 like I did, but if you're like me, hearing from 2 or maybe 3 will give you confidence in your choice.
About the specific types of doctors: I think this matters a lot. Though I have talked to two neurosurgeons, I found the input and experience of my group of specialty ENTs the most helpful. Specifically I think you want to find an ENT who has training and experience in neurotology: that sub-field of ENT deals directly with the sorts of issues caused by ANs. When I was talking to some of the doctors I've included below I learned that a couple of them have treated many hundreds or thousands of ANs, whereas a neurosurgeon may have only treated a dozen (or fewer).
There are a number of doctors in the USA who are very focused on AN issues and who do free "virtual consultations" where you can send them your MRI images and they'll give you their opinion and suggest a course of treatment. If you search these names you'll find many AN patients who have been helped by them. I have been through the process with each of these groups and have been incredibly impressed with their compassion and experience. This may be a good place to start; I reached out via email and phone to set up phone consultations:
If I had to pick only one for you to talk to, it would be the folks at UCSD. They have a patient coordinator who is amazing and is a former AN patient herself. I talked to her for 45 minutes one day about her experience and she REALLY helped me calm down and understand the path ahead.
And, at the risk of speaking from a place of ignorance about your specific case, and again with the disclaimer that I'm not a doctor and only know about my circumstances: if there is not an emergency due to the specifics of your tumor (for example, is it impinging on your brain), you probably DO have time to wait and watch, and to breathe, read, talk to doctors, and allow the "newness" and fear of this situation to decline a bit. It might not seem like that sort of emotional evolution will happen, but I suspect it will: I've had my AN for at least 4 years (probably longer), and now it's just an annoyance in my life rather than something which terrifies me each day.
Please keep posting - we're all happy to help out however we can.
There is a bright future for you on the other side of this.