Hi,
Don't be too paniced by your Mom's diagnosis.
First of all have a look at URL:
www.urologyhealth.org/picturepopup.cfm?id=43 which gives a very understandable diagram of BC.
2cm. of tumor is less important than type so to understand more read Wendy's excellent post explaining HOW serious a given cancer is in the top section of this forum under 'Staging'.
Then do realise that many BCs are very slow developing and if it is just the one when they op. she should be perfectly OK - but never ever let her miss a check up or treatment and even if she has to have regular TURs this is an ongoing process of Trans Urethral Reprieve as you are usually pretey unaware of the Resection side of the deal
On what you have stated so far I believe that your Mom's prognosis has every reason to be optimistic but wish her luck and tell her it is a damn silly place to grow mushrooms
but you get prety used to harvesting if they come back 8-)