Well, that is a horse of a different color.
After BCR, my Rad Onc (RO) at Johns Hopkins (JH) ordered an Ultrasensative PSA (uPSA), which was performed at Quest Labs (I am out of state and 90 mins from a JH facility, and he said that it was fine to use Quest). Quest's detection level is < .02, and my PSA was " undetectable".
FYI: uPSA detection limit at JH is < .03
And, a radiation treatment friend of mine at JH has a different RO, and following the same tx for BCR, he had a regular PSA test and was "undetectable " at < .1
My take is that < .1 is the practical standard to use because I don't think that they treat < .1 anyway
Having said that, I will continue with the uPSA in later Feb and lose my mind when my levels exceed .02, even if they are still < .1
The conundrum of information, or TMI.
Totally understand….still always on your mind.
In my case had BCR about 5 years after surgery waited till number went to .4 decided to do SRT and 6 months Lupron. PSA tests since 2020 have been 0.00. Hoping this will,continue. annual psa test since then.