Hello Salomon,
At 6mm your AN is still at a size where I would think many specialists would tell you that you still have the option to wait and watch or proceed with treatment depending on what you want to do. With a 5 year history behind you, is your AN growing? What size was it when you were initially diagnosed? Are your symptoms increasing or changing and causing you to consider treatment?
My An was 1.8cm when diagnosed and my neurosurgeon told me I had some time to make my mind up, about treatment but he did say sooner would be better than later. In my case within less than a year my AN grew to 2.4 cm, so for me a choice really had to be made. If your AN is not growing, you do not have any symptoms causing you grief, speaking to other specialists as you are planning to do is a really good idea - you just might find that you can wait and watch a little longer, if you choose.
Best of luck and welcome to the forum.
Cathie.