It goes roughly in line with age, Rob, so about 70% of men have prostate cancer at age 70, about 80% at age 80, and so on. Localised prostate cancer is EXTREMELY unlikely to kill you. The 10 year survival rate is 98%; the 15 year survival rate is 95%, so a diagnosis is far, far from being a death sentence. Do try not to worry. Wait until all the diagnostic tests are done, which unfortunately does take a while.
Best wishes,
Chris