Just wanted to respond to one part of your post, usually the 5/10/15 post treatment years refers to a BCR (biochemical recurrence) of cancer. For example, if someone has surgery then PSA should be "undetectable" and if PSA is no longer undetectable then that is considered BCR. It does not mean that cancer has necessarily returned, it surely does not mean it has spread, it just means the PSA number has risen above a threshold. Odds of BCR are calculated in like 1/5/10/15 years. Then sometimes 5/10/15 refers to life expectancy, but PCa usually grows so slowly that when relatively mild cases (like yours apparently) are caught early (like yours) and treated then life expectancy is not shortened by PCa (long way of saying a mild treated case of PCa isn't going to kill someone in 5/10/15 years).

You are going through correct steps and you will get good advice here. Probably will want to have a decipher test on the biopsy tissue, see how aggressive the tumors are. You will probably want to get genetic testing of your dna, to see if you have any mutations that make cancers likely. Might want to consider a 2nd opinion from a National Cancer Institute Center of Excellence.

I was about your age when I was diagnosed, went on Active Surveillance for a few years, got an MRI then a year later a 2nd MRI and another biopsy. At that point I chose treatment and for me I selected surgery. It's a big decision but keep researching and best wishes!