I'm far from an expert, but my guess is that healing from removal of a tumor that size might take awhile, and that there might be bleeding afterward for a longer period than with smaller tumors. As Mike said, a ping-pong ball size is on the large side for bladder tumors, at least those of the papillary type (the kind that stick out from the bladder lining). CIS (flat tumors) may be larger in diameter, but I don't think a doctor would describe that type as being like a ping-pong ball.
Best of luck with your appointment!
Ann
Small TA Grade 1, May-06; recur (2 tiny), same, June-08; TURBTs both times. BCG begun July-08, dosage to 1/3rd May-10, completed treatment December-11. All clear since 2008.