You have already received a lot of excellent information, but I just wanted to add a little hope.
I just joined this forum, as my cancer has returned again after RP surgery, and radiation.
The hopeful part is, my surgery was 19 years ago, and I still feel wonderful at the age of 75.
I feel fortunate, but it also says that your dad could outlive the post operative life that I plan on having.
You need to listen to some of these people that are more informed on the newer treatments than I am.
I do want to wish and pray for your dad to have the best outcome, regardless what treatments he has.
PS I loved the time I spent in Denmark, but this was back in the 1950's. It was a beautiful country with beautiful people to visit with.