Hello Greg... Welcome to our forum. So sorry you have received this unsettling news of "abnormal" cells. It's hard not to jump to the worst conclusions, which is definitely scary.
As I'm sure your doctor has probably discussed with you, a recurrence is possible. Even so, that would not necessarily mean cancer has spread elsewhere. There are members here who have had to go through multiple rounds of BCG due to annoying recurrences, and have done well with that regimen. A diagnosis of high-grade does require very close monitoring so it is good that your doctor is getting you in to check things out right away.
I know it already feels like it's been forever since that phone call while waiting for your next appointment. Please let us know how things go and I am sending wishes for the best possible outcome from your RPG.
Best wishes... Catherine
TURBT 1/21/10 at age 55
Dx: T2aN0M0 Primary Bladder Adenocarcinoma
Partial Cystectomy 2/25/10
Vanderbilt Medical Center
Nashville, TN