I would have gone through PM, but since you can't, I was diagnosed 5 years ago, had surgery, No problems since (can't actually say Cancer Free til you hit that 5 year mark).
Anyhow, as I'm guessing your Doctor told you, just about Any form of treatment you decide on will have a very high success rate provided you were diagnosed in the early stages. And since Prostate Cancer is typically one of the slowest developing cancers there is, chances of a Full recovery and normal life are outstanding!!
You don't mention if you have already had surgery/radiation treatment, etc. but if you have and now you are wondering if the 'Plumbing' still works, be assured that you will be able to get hard, you will be able to have intercourse, and you will definitely enjoy it.
A little biology lesson:
The Testicles are where the semen is produced, the Prostate Gland is where all the other fluid (cum for lack of a better word is produced) remove the prostate gland = no cum. Sounds like a real bummer doesn't it?
Not so much. That was my biggest fear also, but it turns out that the Brain, where the pleasure centers are, doesn't really know if your body is spouting cum during orgasm or not. In other words, you still get all of the pleasure, a lot less mess! When you get off, you still GET OFF!!
Finally, sometimes we older guys need a little help to get up with or without prostate cancer. Not to worry, if the little blue pill helped you before, chances are, it still will. If it takes a little more help now, talk to your doctor. There are a variety of options available to ensure that you have a rewarding sex life!!
One thing I will tell you for sure is that you will enjoy your encounters even more than in the past!