Newly diagnosed and very confused. Is staging and the gleas

newly diagnosed and very confused. Is staging and the gleason measure the same thing? My doctor is sending tissue for additional exam (another 3 weeks before it returns) to determine aggressiveness. What is this? I am a healthy, active in every way 75 year old male. Before I give up our sex life, I want to better understand my risks and treatment options. The urologist pretty much said radiation or surgery. He said my cancer is small on one side of the prostate and a 3, larger on the other and a 4. Is this a gleason number? A staging number? Are they the same?

I found this info for you....I hope it helps....your doctor should be able to answer any other questions .
http://www.tackleprostate.org/the-gleason-score-and-staging.php

@TennisPlayer thanks. simple and clear explanation. I get it now. Thanks!