I once had a urologic oncologist tell me that the vast majority of older men will have some low-grade prostate malignancy found if they have biopsies. The older you get , the more likely it is to happen, so it isn't a big surpirse if prostates removed at cystectomy show unexpected prostate cancer, especially if the men are older as the incidence increases with advancing age.
That's a different issue than the question of whether or not the treatment for prostate cancer increases the incidence of bladder cancer.
-Warren
TaG3 + CIS 12/2000. TURB + Mitomycin C (No BCG)
Urethral stricture, urethroplasty 10/2009
CIS 11/2010 treated with BCG. CIS 5/2012 treated with BCG/interferon
T1G3 1/2013. Radical Cystectomy 3/5/2013, No invasive cancer. CIS in right ureter.
Incontinent. AUS implant 2/2014. AUS explant 5/2014
Pediatrician