Hi Debbie, everything possible has been thrown at your husband’s PC. The way he has coped with the treatment and the response to it is excellent.
As Lyn says PSA will rise, he still has a prostate so that is to be expected as the healthy prostate cells recover from the ondlaught.
I looked up cancer research uk and they have the same defintions as seem to be used across the world for biochemical recurrence.
PSA levels after treatment
After surgery to remove your prostate (prostatectomy)
PSA levels are usually extremely low (below the normal range) about a month after surgery. They should be < 0.02 ng/ml. If it increases above 0.2 ng/ml this can indicate recurrence.
After external beam radiotherapy
PSA levels usually get lower slowly over months or years. Defining the limit for cure is complicated and you should ask your cancer specialist. Usually a level of 2 ng/ml above the lowest point after treatment (the nadir) is taken as a sign of recurrence, or 3 increases in a row (consecutive increases).
After internal beam radiotherapy (brachytherapy)
PSA can rise temporarily after brachytherapy. This is called PSA bounce. The level then lowers slowly. Usually a level of 2 ng/ml above the lowest point after treatment (the nadir) is taken as a sign of recurrence.”
The oncolgist is being very proactive by wanting to see him if PSA reaches 1.0, that is a good thing.
Hopefully your husband will remain cancer free now.
Best wishes, Ian.