Labcorp has indeed changed its uPSA undetectable back to <0.006 ng/mL

After reading these types of threads, my once scientific minds keeps telling me, 'don't sweat the little stuff'. ;-)

Hi WeightLoss. Yes, most labs have a "standard" PSA test designed for men with untreated prostates. But I would be very surprised if you can find where Quest states that the undetectable for their 5363 test is <0.10 ng/mL. That's because the next higher readings one would get using this test are not 0.10 followed by 0.11, but rather 0.1 followed by 0.2. I believe the undetectable for this test is <0.1. You would see that and not <0.10 on a report Please let us know if you find otherwise -- thanks.

Quest chooses to call its other more sensitive test (<0.02) "post-prostatectomy" -- other labs call theirs "ultrasensitive". Looking back, ultrasensitive was first used to describe tests with one decimal place, then two, and now two or three. Post-prostatectomy does capture the idea that this degree of precision is really only useful after a RP and not RT, and, as discussed many times in the Forum, it's not needed for most RP patients. The literature uses only ultrasensitive test; I believe post-prostatectomy is used only to refer to the timing of a test.

You (at a walk-in lab), your doc, or a lab tech should always order a test by number, for example, making sure the number is on a pre-printed lab form or adding it. More than one of us (me included) have gotten a result, only to find it was done with the wrong PSA test. Sometimes the lab has enough blood that is within the acceptable time-frame to rerun the test; otherwise you need another draw if you want a different test.

Djin

Do you think Quest's "regular" (less sensitive test) goes down to 0.12, 0.11, 0.10, and <0.10 and their uPSA goes down to 0.03, 0.02, and <0.02? They may as well ditch the regular test. I'm saying I think the regular Quest is a single-decimal that goes down to <0.1 rather than <0.10 and then goes up to 0.2. Unless someone has an actual Quest result with <0.10.

Your x.xx test (going down to <0.10 and not a Quest test), seems to me to be a 2-decimal uPSA test that after <0.10 continues upward with 0.10, 0.11....

Am I barking up the wrong tree? I'm distinguishing the number of decimal places reported from the lowest value reported.

Think of it this way. Say that LabCorp, instead of dropping from <0.014 to <0.006, dropped to <0.010. The rightmost zero is a significant digit; it also means the next higher values are 0.010 (without the <) followed by 0.011.

Anything is possible. I'm assuming (yes contains ass) that labs are careful about reporting. The same clearly may not be true for transcribed numbers. After my jump to 0.034, I was awaiting my next test result, which my uro reported on the practice's portal before it was released on Lacorp's. It showed 0.02 and I thought good, but
wait-- perhaps this was a mixup and a different test and the 2 may have been rounded and not precise. I messaged the oiffice and it was actually 0.020 and the same LabCorp uPSA test we'd been using.

Post Edited (DjinTonic) : 8/7/2021 6:04:35 PM (GMT-6)