Its an extremely difficult decision. I am 36, was 35 at time of diagnosis with T1G3, but with angiolymphatic invasion and multiple sites, with CIS. The evidence for this particular type of disease is unclear, and I took the pragmatic view that this was likely to behave more like a T2 tumor. I had a cystectomy and neobladder, and also underwent 3 months adjuvent chemo (MVAC).
It has been a difficult year, but worth it for us as a family. We decided that despite the risks of the surgery and chemotherapy, we were not prepared to discover tumor at a more advanced stage after TURBT and bladder/local chemo.
As I said at the beginning, it was a difficult decision. We will never know whether I could have 'got away' with bladder sparing treatment, and luckily I managed to survive the chemo without too much trauma. I am still getting to know my bladder, but am fit and well, and able to mountain bike better than I have for years.
Good luck with your decison, and best wishes. Andy.