markww11,
Welcome. I'll get straight to your question! CIS or carcinoma in situ is a rash like/red irritated area in the bladder. It is always a high grade tumor that does need to be addressed that normally won't show up on a CT scan. At the same time it can be just cystitis or inflammation hence the need for the biopsy. As we are all volunteers and not doctors I won't guess what your situation is except to say wait until the biopsy is done with the pathology reading. Sometimes it is even something else such as stones irritating down from the kidney. Waiting is the hard part. It appears you are getting all of the right tests done to determine what this is. Keep posting as you go with any other questions.
DX 5/6/2008 TAG3 papillary tumor .5 CM in size. 2 TURBS followed by 6 instillations of BCG weekly with a second round of 6 after a 6 week wait.