Anyone “below detection" with an ultra sensitive PSA test?

@melvinw Ultrasensitive PSA is medically meaningful in my specific situation (stage 4b, currently fully suppressed with ADT+Erleada):

< 0.01 (not detectable) means anything borderline that shows up in scans doesn't require too much additional investigation, beyond some follow-up scans to ensure it's not changing

>0.01 (detectable) could trigger biopsies or other more invasive tests for a borderline imaging result (or in the case of my thoracic spine, precautionary radiation, since the spinal fusion means it can't be biopsied).

My original cancer was very aggressive — I went from a twinge in my back to paraplegic in about 5 weeks — so I don't necessarily have the luxury to wait and see if something starts growing again.

I also recognise that my case is atypical (my original oncologist told me only about 5% of prostate cancer behaves like mine did).

Agreed that once it's detectable, it doesn't matter much whether it's 0.02 or 0.05.

after i started ADT in July'25 and radiation in early Oct'25, my PSA went from 71 to < .02 ( Oct 26th) and after Dec it has been < .01 ( last draw March 26 )

. hope it stays down..it is nerve wracking each 3 month draw..

This article discusses implications of uPSA value of 0.03 after RP - according to this research this specific value predicts BCR in making. I am posting this just to say that uPSA has its value and predictive potential in some circumstances.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4527538/

@melvinw LabCorp charges 5x as much for uPSA that goes to .002 vs. their standard that goes to .1; so now more of a commercial / marketing reason (LabCorp is the only one to go to 3 decimals) vs. medical. The standard Quest PSA goes to .02 and is priced competitively with LabCorp's standard PSA. Most labs report to 2 decimal places on standard PSA tests now. There are over 5 different methods of PSA lab analysis. Quest, LabCorp std., and LabCorp uPSA use 3 slightly different methods. That is why it is recommended to get the PSA with the same lab. LabCorp may report standard PSA to 1 decimal to market their uPSA test. Other labs us the same PSA analysis and report std. PSA to .02.

Yes, < 0.01 is typical depending upon the ultrasentive lab test equipment. Others receive a report of < 0.003. Your test lab can confirm the sensitivity .

@surftohealth88 Thanks for that article. Really provides an answer to my question about the clinical value of uPSA tests. As is usually the case, there is no one-size-fits-all approach to surveilling for a recurrence. My old urologist, who retired, used to say, ‘The data aren’t the problem, it’s how people use the data’. Wise words.

Interesting that the article questioned the use of 0.2 as the PSA value for defining biochemical recurrence. They advocated for a lower value given that uPSA could detect the trajectories toward a BCR at PSA values < 0.1. My salvage RT was initiated when my PSA was 0.11. None of my docs suggested waiting for my PSA to rise higher. Of course, the presence of a palpable nodule in my prostatic fossa that glowed like a Christmas tree on the PSMA PET scan weighed heavily in moving forward with treatment.

Anyway, thanks. I’m seeing the bigger picture for the use of uPSA testing now.

@jim18 Thanks, great info. Yes, from here forward I am using the uPSA test from Labcorp. I even go to the same collection center and always check to see if the sample was analyzed at the same lab.

@jim18 Yes, my hospital lab goes only down to 0.01, not 0.002. OTOH, I get the results in a couple of hours, since they do the test in the same hospital campus (they stop by every hour on the half-hour at the clinic with a cart to pick up the samples and wheel them to the main hospital lab, and I can almost predict when results will pop online now, based on when they draw the blood).

Cost isn't an issue here in Ontario, fortunately. I didn't ask for uPSA, and didn't even realise I was getting it at first: it seems just to be the default for someone under the care of the regional cancer centre.

I'm sure the routine annual screening test, for those who've never had prostate cancer, is still down to only 0.1, but you wouldn't have that done by a hospital lab here.

@topf Thanks! Hope your PSA stays way down there.

@northoftheborder Thanks, this provides insight into the value of uPSA testing. I’m seeing the bigger picture now.

Yeah, my case is atypical too, but in a way much different than yours. My urologist told me after my salvage RT that it in his experience, it was rare to see a guy with a palpable nodule like mine that didn’t have a higher PSA and distant mets. I’m happy to be the outlier.