Struggling with Worry - High PSA after Prostatectomy

My husband had a radical prostatectomy four months ago. His Gleason score was 4/3 - lymph nodes were clear - doctor at Mayo thought he got it all. At 3 months, his psa was 5.0. Yes, that is correct! He had it rechecked - now 5.2. At the time of surgery, they did the nuclear imaging and didn't see any cancer in his bones.

I am assuming he will likely have radiation next. Can anyone share a story of hope? He is quite down, as am I? He is at the best hospital in the world. His father died of the disease at 68. Anything we should be doing that we aren't? He just sent off his latest psa lab work to the doctor. I really love this guy.