So sorry that you are here....but glad to meet you! It is hard to wait until the uro appointment, I know.
I am going to play a guessing game here....and I wonder if your diagnosis might not be CIS....carcinoma in situ. It IS high grade, and appears more like a rash than a protuding tumor. IF IT IS CIS, and if it has not spread into other layers of the bladder, it will most likely be treated with BCG.
Please remember that this is just guesswork on my part...I an not a urologist and it is impossible to make a diagnosis from what you have provided!!!
You can read a lot about BCG on this Forum....but it wouldn't be pertinent until you have a definitive diagnosis from the urologist.
I was diagnosed with CIS, had a complete series of BCG, and am now on my fifth year...all clear!!
Best of luck to you, and please keep us informed!