Intravesical BCG is highly effective in superficial Bladder cancer with usually mild to moderate side effects. If it does not work or goes invasive then surgery or some bladder sparing protocols can give good local control and sometimes allow the bladder to remain and function normally.
Interestingly , I am not aware of a bladder sparing approach for superficial that has been reported although it should work . It may be an option for a person who is motivated and will undergo close followup as with any bladder sparing approach.