First, I don't think that you and your dad understand the situation with non-invasive transitional cell bladder cancer, which is the kind most of us are diagnosed with. IF it is low grade and early all that might need to be done would be removal of the tumors by TURB. If it turns out to be high grade, BCG would be a consideration.
Only if the cancer has spread (and you won't know without the TURB) would traditional chemo even be considered. Radiation is not the treatment of choice for advanced bladder cancer in most cases. IF the cancer has spread (and your dad does not know this) that would be the time to consider whether treatments such as chemo are indicated for him.
I suspect that Alan agrees with me that NOT having a TURB is choosing discomfort and illness down the road that could be avoided. Yes, a TURB requires general anesthesia. However, it is usually a very minor procedure (which is not to guarantee that he might not have problems.) I much prefer it to dental appointments, but then I am dental-phobic (should mention that my late husband was an oral surgeon!)
IF it turns out to be worse than we expect, THAT is the time for the kinds of decisions your dad is considering. I realize that this IS a personal decision, but had to share and expand my thoughts. Won't mention it again.
Best of luck to both you and your dad.
Sara Anne