Type 2a bladder cancer

I will be starting treament soon. I have been seen by two Dr. the first just wanted to go in and remove everything. The one I am now seeing  is going to try treatment he is in Abany Ihe took over one hour with me and answered all my questions. There is one thing I do not understand. He said if after two months of treatment and there is no improvement the bladder and prostate must be removed. I asked why my prostate there is no cancer anywhere in my body just a small one in the lower left side of my bladder Ihe stated to me the prostate is removed because it is normal pratice he also stated that in cases the the prostate was not removed there was a issue with cancer. I am not sure where to find the facts regarding this.