I was diagnosed with high grade non-invasive bladder cancer over 11 years ago and am still fine, with no signs of bladder cancer. (pTa means the bladder cancer is still confined to the very top layers of the bladder and has no signs that it has gone any further....a "good" diagnosis!)
The lupus is a complicating factor, of course. So whatever treatment your father has needs to be coordinated with all his physicians. For non-invasive bladder cancer, there is no additional surgical treatment. BCG is the treatment most used when the cancer is high grade and it is very effective in over 70% of the cases. There are many of us here on the Forum who have had it and are doing great. It does have its side effects, but they are nothing compared to what people who need systemic chemotherapy go through. IF your dad does have BCG there is lots of information about it on this Forum if you just use the SEARCH function. There are other options than BCG such as Mitomycin, that are not quite as effective but are used if a patient is not able to receive BCG.
Since lupus might be a complicating factor in your dad's case, a consultation at Stanford would not be a bad idea. It is an excellent place for bladder cancer treatment.
It is great that you are an advocate for your dad and that he does not need to go through this by himself. The odds are that he will be fine!!
Sara Anne