My stepdad had prostate cancer 20 years ago and its been in remission with no signs of it returning. When he was diagnosed treatment was a lot more aggressive, with pretty serious side effects from a boy side of things ;-) My god father was recently diagnosed too, and his treatment was successful and without the, er, downside to go with it.

Like MG said, if you're a guy and you're going to get cancer, its definitely the one you want.

Good luck to you and your dad. However "good" things look, that C word is scary as hell.