Apparently, there is a study conducted by Xtandi. This were randomly selected to include all different levels. Their conclusions is those who were given ADT + Xtandi had a recurrence rate of 10%. That would be somewhat at odds with your figure, which is possibly drawn from an older study. The science has made such progress some times the studies do not catch up. So do give you a warning in the footnote that the study may not be current etc etc.
The presumption here is if you have chemo on top, ie triplet treatment, the outlook would be even better.
At the end of the day, regardless of staging, it depends on your treatment and how well you respond to it. The best case is if the PSA falls by 90% in the first month, and < 0.1 within 4-6 months.
Some may have stage 3 but does not respond well. That may be more serious than stage 4 that responds well.
Also remember that recurrence does not necessarily mean terminal as far as PC is concerned.
Dont mind me. I am just another layman trying to make some sense of the whole thing.