Typical Plan When Post RP PSA goes from < 0.02 to >= 0.02?

I'm confused as well.

I believe that it means that PSA is undetectable.
And PCa, therefore, is not detectable.
So I would interpret undetectable as "cured" or in remission.
Hopefully never to be heard from again.
Sorry; that's the best I have.

@dlachn @wellness100 Tests use a chemical/mechanical process which work within certain ranges. If the results of the test are out of range for that test, they are recorded as out of range, hence the < sign in some results. Some derivative medical reports, like on a portal, may report results of tests without detail. The detail is best found in the original report, which is nowadays often available directly to you from the testing provider, like Labcorp or Quest Diagnostics.
Since those chemical/mechanical processes (assays) are different, results are not directly comparable. While they should be close, since they are measuring the same thing, individual measurements may vary slightly. This is particularly true when trying to measure very small numbers, like on an ultrasensitive PSA, sometimes abbreviated uPSA, usPSA, or USPSA.
For example, my uPSA readings (in sequence) have been 0.012 ng/mL, 0.016 ng/mL, 0.012 ng/mL, < 0.006 ng/mL , and 0.020 ng/mL. Looking at these numbers we might suspect that they are being reported in intervals of .004, since they are all divisible by that, and that anything below .008 is reported as < .006 as outside the range of this test. There are several kinds of accuracy with tests. One is precision, as to the nearest .004, another is test/retest reliability. For instance, if the test/retest reliability were one interval, then .012, .016, and .020 could all be within the same range, one interval from .016. If there were also an error in measurement and/or interpretation on the < .006 measure, which is also a real possibility, then these all could be measuring a constant value!
On the other hand, the uPSA could have been decreasing over the first 16 months after surgery, reached a nadir (low point) of being undetectable last summer, and now is starting to rise, on a trajectory that could put me at 0.100 in another 18 months, which would be not untypical for recurring PC (prostate cancer) after RALP (radical prostatectomy) showing up about 3 years later.
So, yes I'm concerned, but no, I don't know which of these is the case. My urologist may shorten the time frame until my next test to get more data points given the rise in this reading, just like he lengthened the time frame (from 4 to 6 months) after the last reading.
The note on the labcorp patient report says as follows: "Roche ECLIA methodology. According to the American Urological Association, Serum PSA should decrease and remain at undetectable levels after radical prostatectomy. The AUA defines biochemical recurrence as an initial PSA value 0.200 ng/mL or greater followed by a subsequent confirmatory PSA value 0.200 ng/mL or greater. Values obtained with different assay methods or kits cannot be used interchangeably. Results cannot be interpreted as absolute evidence of the presence or absence of malignant disease."
[I have not seen any technical data to back up my hypothesis about the readings, but you can also imagine that this might not be published anywhere I can find. The various assays may even be patented, copyrighted, or considered confidential intellectual property by various private companies and partners. If anyone on this forum can direct me otherwise, I'd love to know 🙂 I did just find an article comparing non-ultrasensitive PSA tests https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8627779/ from 11/2021 and here is a testing procedure reference doc for the Roche non-ultrasensitive PSA https://labogids.sintmaria.be/sites/default/files/files/total_psa_2018-06_v13.pdf ]

It is confusing. If the lower limit of the test taken is 0.1 or 0.02 how can the results be reported less than these numbers using a less than sign.

Reviewing some of my previous notes and collecting more info and getting a couple emails from other PCa survivors, what it appears to basically boil down to is it is up to the Urologist what test with what precision to use based on their chosen balance between what they consider actionable numbers while avoiding causing the patient unnecessary concern/anxiety. On the tests reporting 0.1 and above, the actual precision is probably 0.05 but the Urologist has chosen a non-ultrasensitive test because they feel there's nothing to act on until it reads 0.1 or above. On the < 0.02 the Urologist has chosen an ultrasensitive test as they may want to more closely monitor the trajectory at 0.02 and above and possibly recommend salvage treatment earlier. But I'm guessing the accuracy on that test is 0.005 or 0.004 like spice said. Even it was accurate to 0.001 increments, there's really nothing do act on when the reading is < 0.02 or even 0.03. It starting to look like 0.02 is sort of the modern cutoff as to when you may want to test more frequently to see if it keeps going up.

This is why anyone getting results to three decimals has always perplexed me as to what's the point of that level of precision. There is nothing to act on if PSA is reading 0.016, 0.014, 0.010, 0.005. Even if it's rising. Yet a patient could get anxiety over seeing rising results only to see their 0.016 go back to 0.010 3 months later. All Urologists would say there is no cause of concern, this is still considered undetectable and no change of plans, just keep testing (usually every 3 months the first couple years then every 6 up to year 5, then once a year.)

The definition of biochemical recurrence of 0.2 is WAY outdated based on dozens of studies over the past 15 years showing the ultrasensitive PSA can accurately predict biochemical recurrence at lower levels. It seems as more data is accumulating the statistical consensus is forming that o.o3 almost certainly predicts biochemical recurrence but 18-24 months in advance of when you would hit 0.2.

It sounds like these days for the top Urological Oncologists to possibly recommend testing every 2 months instead of 3 if you hit 0.02 or above to establish the doubling time and/or rule-out that it's just a fluctuation not related to recurrence. I've seen on patient report of his PSA fluctuating between 0.01 to 0.04 and not going above 0.04 but that may be 2 or 3 patients in 100 according to stats from studies that don't have a recurrence once they hit 0.03.

Newer data shows clear advantage of treating before 0.25. At least one patient confirmed their Urologist initiated salvage radiotherapy when PSA had at least three consecutive rising readings of 0.02 or above and reached at least 0.05. This maximizes the chance of killing remaining cancer cells in the prostate bed prior to micrometastases moving farther out when the PSA is higher. Other Urologists may do testing that only goes to 1 decimal and don't recommend any action until you get a reading of 0.2. Frankly I'd get a new Urologist if this is the case as this is thinking based on outdated information in my opinion with the exception of when you factor age in. There's a difference in the decision making when you are 55 like me and when you are 75. In many cases if normal life expectancy is 10 more years or less salvage RT is probably not going going to extend the person's life especially if the PSA is < 0.2 (in my opinion) They will die of something else before prostate cancer. If you have 30 more years life expectancy, you want to initiate salvage treatment as soon as possible in my opinion when the numbers reliably confirm a recurrence. I think a reading of 0.05 with at least 2 consecutive rising readings over 6 months leading up to that might be a good cutoff but this is a matter of opinion.

The less than sign means that the test did not detect concentrations within the limits that the test can accurately measure. The standard test for PSA has a lower limit of 0.1. The ultrasensitive PSA used by Quest Diagnostics, a common testing lab, has a lower limit of 0.02. The uPSA used by Labcorp, another common testing lab, has a lower limit of 0.006.

There are two related things being monitored with uPSA--absolute value and change compared to last time. If there are not tests at intervals, when the value gets to a significant level, there is no prior data to show how fast it has been changing. Generally they are looking for absolute values of at least 0.03 (Johns Hopkins and 1 other, I think,) but more typically these days 0.10, and three tests in a row with rising values.
However, as you say, there are some who are more aggressive than others, for the reasons you discuss. There is also debate about whether rising values are sufficient to act without an absolute value, and if so, rising how fast. This is not currently a clinical standard as I understand it, as studies have not confirmed its relevance.

Welcome, @dlachn. Are you currently in treatment for prostate cancer?

Yes. DaVinci robotic prostatectomy performed in July 2011. Relapse, 40 salvage radiation therapy was completed in Nov 2012. Androgen deprivation therapy was initiated in Jan 2015 for one year. Lupron was again given from June 2018 to Sept 2018 . Lupron was next given from June 2020 to Dec 2020. 20 Salvage XRT was given to right external iliac adenopathy in Summer 2020. PSA has slowly risen to .82. In the next few weeks I will be meeting with my urologist to determine when to do a PSMA.

I am 70 had a robotic prostatectomy 9/22. For the first year every 3 months my PSA was < .02. I just had a test at 18 months and it was .03. I got the test because I have had a low grade fever for three weeks after antibiotics for pneumonia and the pneumonia appears to be gone. They did a complete set of blood test. I am getting another set of blood test next week if the fever does not break. The question I have should I ask my urologist about the .03 if the new test comes back at the same value. I am scheduled for a PSA with my urologist in two months. From reading above the .03 can be significant since it is increasing but it not at a point where anything will be done which appears to be somewhere between .1 and .2.
I have had many problems since my prosectomy due to hypersensitivity of my pudendal nerve, the nerve was hypersensitive prior to surgery but after surgery I had bad sitting pain and other pains. After a pudendal nerve block the problems after surgery is gone but I still have penal pain, urinary frequency, and urgency along with stress incontinence. The frequency is destroying my sleep. I am getting so frustrated because every time I think I am getting better something else happens. I have lowered my goals to get sleep and lower the pelvic pain since both of these can affect my being able to visit my grandchildren. The other things I can handle with protection. The fever impacted me because I had a week scheduled to see my grandchildren but not knowing if the fever is contagious has cancelled the trip. I am trying to take small steps since stress causes mor pelvic pain but I need to see my grandchildren, this is my life.
Wishing everyone happiness always