Mark, you're NOT alone. We've all been there, and we know how horrible it is waiting for results. Try to do something mindless to occupy yourself with - clean out a cupboard or paint the garden fence or something like that. Try not to make assumptions about whether you'll get either good news or bad news tomorrow. What will be, will be, and there's nothing you can do to change it.
Write down the list of questions you want to ask the urologist tomorrow, and take that list of questions with you into the meeting. I remember that as soon as he said "you've got cancer" to me, I basically blanked out and everything after that was a blur, which is not the ideal way to do it.
Finally, remember that if it turns out that you do have cancer, it's not the end of the world, and it's not a death sentence. I was told in my meeting that I had not one but two different cancers, and three months later one's been fixed, one's well on the way to being fixed, and I'm enjoying life again.
You may think "I can't get through this", but you will. Just take it a day at a time and remember you're not alone. We're all here to support you, as are the PC-UK nurses.
I wish you the very best of luck for tomorrow,
Chris