Ultra-sensitive PSA Following Prostatectomy Reliably Identifies Patients Requiring Post-Op Radiotherapy

[RMontana]

uPSA Ultra-sensitive PSA Following Prostatectomy Reliably Identifies Patients Requiring Post-Op Radiotherapy

Using first postoperative PSA cutoff ≥0.2 ng/mL has only 46% sensitivity to detect failures. If the relapse cutoff is lowered to first postoperative uPSA ≥0.03, sensitivity substantially increased to 70% (Table 4).May 1, 2016

Any post-op PSA ≥0.03 captured all failures missed by first post-op value (100% sensitivity) with accuracy (96% specificity).

Defining failure at uPSA ≥0.03 yielded a median lead-time advantage of 18 months (mean 24 months) over the conventional PSA ≥0.2 definition.

uPSA ≥0.03 is an independent factor, identifies BCR more accurately than any traditional risk factors, and confers a significant lead-time advantage.

Biochemical failure precedes distant metastasis by about eight years

A meta-analysis quantified the success of salvage RT to decrease by 2.5% with every 0.1 PSA increment [10].

Benign uPSA patterns occurred in the range from 0.01 to 0.02 ng/mL, sometimes persisting over several repeated PSA draws.

Once the threshold was increased to uPSA ≥0.03, nearly all patients (98%) eventually relapsed (Figure 1).

Specifically, initial and continual monitoring with uPSA out to at least 5 years and at intervals not longer than 6 months between tests so that eventual failures can be identified earlier and postop RT can be initiated with a greater likelihood of success.

use of the conventional assay and cutoff (PSA ≥0.2 ng/mL) is flawed.

data showed that about half 50% of relapses missed by conventional PSA relapse criteria would be anticipated with uPSA.

The majority of our patients had uPSA failures within the first three years (82%) but a substantial number (18%) relapsed much later and therefore a closer PSA surveillance probably should extend to a minimum of 5 years.

ART (adjuvant)is better than delayed SRT (salvage), ADT (androgen deprivation) alone, or neither.

ncbi.nlm.nih.gov/pmc/articl...

[FlyJ]

That article was written over 7 years ago and seems very legit. I wonder why using post op uPSA hasn't become SOC?

[RMontana in reply to FlyJ]

Good question...AND no one in the USA reports uPSA...at my cancer center while I was treated they went from reporting 0.20 PSA to 0.40 PSA as their base level...meaning, they report you as being non recurring at that level...being an overseas worker and having had access to uPSA for my entire treatment history it drives me crazy when I get tested in the USA...they wont go below 0.20 or 0.40 which for me is too high...that is what these papers are reporting...now, I am sorry for our fellow men in these various groups who are way beyond these levels, but for those who are coming along and have this option its good to know...push your Doctor to get your uPSA levels reported, or find a Lab that will do it...TNX

[Ribotom in reply to RMontana]

One thing to note about the Kang et al paper you discuss is that their cohort is all high-risk patients (pT3/4, EPE and/or positive margins). So there is no reason to think from this paper that a new definition of BCR based on a uPSA value of 0.03 or higher would be useful for INTERMEDIATE risk patients.

One thing about the paper I find a bit puzzling. For patients treated from 2006 onwards, they switched to a different assay (Roche Elecsys, E170) which has a lower functional sensitivity than the Access Hybritech assay they used until 2006. In fact, they say that the functional sensitivity of the Roche assay is 0.03, which is equal to the PSA value they recommend as a better definition of BCR for high-risk patients. I am surprised that they got such good specificity with this new definition, if they are indeed working right at the limit of the assay.

My own recent experience with these two assays has been that I continue to be undetectable with the Roche assay (now <0.006) while my Access Hybritech numbers have gone from <0.01 to 0.01 to 0.03 over the last few months. I don’t know for sure whether both assays are calibrated to the same standard ( ie Hybritech or WHO) but I think the numbers should be a bit more in agreement than a fivefold or greater difference. Time will tell. If the Access Hybritech assay eventually shows me at 0.10 or higher, presumably the Roche assay will start to give a detectable number.

[RMontana in reply to Ribotom]

Interesting...I want to keep tracking my PSA at the uPSA levels and need to find the Lab that has the right assay to match what I need. I did not know that...but my point in this discussion is that, for those who can start at the uPSA level to track this disease start there! Dont wait for it to grow to the normal PSA levels of 0.20 and higher; why! The SOC waits way too long to act in most cases with our disease and we as men can gamble that we will be on the right side of the distribution curve for progression but if you guess wrong you cant come back the next day and watch the new version of a game show...this is for keeps. So as an Engineer I opt for prudence and want to know as soon and as low as possible if I have a problem. I want to act our front and choose the least evasive treatment...we need to be our own best advocates. Doctors are busy; they are also stuck in the mud on a lot of new developments. I can tell you mine were...TNX

[Ribotom in reply to RMontana]

Are you in the USA? I am using Labcorp for the Roche uPSA test. The other assay (Access Hybritech) is used by my docs. When I had my RP in 2020, I didn't start off wanting to get both sets of numbers -- I just did not want to wait a full 3 months to get my first post-RP reading, so I paid out of pocket for the Roche assay at Labcorp. I knew even back then that the different assays are not interchangeable, but seeing that first undetectable uPSA reading was reassuring. Anyway, best of luck with your journey!