See table at end of this posting for data being referred to here.
PSA has been going up for 2 1/2 years, starting a few years after inital IMRT
(no surgery was done)
Before lab of 12/30/2016 as shown below, the increases had been at a regular
rate, going up either 0.2 or 0.3 every 5 weeks when the lab was done. (am not concerned with psadt (psa doubling)here for this discussion)
And it always used to increase with each lab.
However, since 12/30/2016, some of the labs have either stayed the same
as pervious ones or even gone down a bit, and then the lab results
from a subsequent test after that shows the value of where it would have been
had it kept going up at the rate it had in the past.
And this pattern seems to be repeated - see chart below.
I've read about psa variance and find just a relatively few references online,
some relating to that psa can vary even within a day, but also a week or time of day
or season of the year, etc - according to some studies. Some articles seemed
to mention it can vary those ways by 20 to 30%.
Am also aware that there are 2 calibration standards used by different lab equipment manufaturers -
and as a result, the psa results stated can vary up to 20 % on the same blood sample -
, due only to those 2 different standards, and thats why I think its another reason
why people are recommended to use the same lab - assuming of course a given lab
uses just one manufacturer equipment/calibration standard for doing the psa testing,
Each lab I have done always says it was done using the Roche ECLIA
methodology -
and I was told by Roche that the calibration standard used by their machines
is the WHO standard, so am assuming that the same calibration standard has
been used for all my tests for many years.
The psa tests were not ultrasensitive ones.
I don't think these variances are psa bounces in context of post IMRT bounces -
since the IMRT was completed 5 1/2 years before these patterns were seen.
And since before the dates below, the psa kept going up once it started
back up. I do recall several bounces in the first 2 years after IMRT.
I've had no adt, no other rx or treatment that might affect psa, no new rx than the 2
have been taking for a long time, no change in rx dosage, no changes in diet
and before psa tests, as for many years, no ejaculation or exercise bike usage for several
days before the test. And I always go at the same time of day to the lab.
===> Thus am wondering, could the pattern I'm seeing of psa being the same or lower
on subsequent tests, before returning to where it would have been given
previous trends -- could that be due to some problems at the lab ?
Or is it really related to some natural and expected psa variations,
even weeks apart and even though before 12/2016 labs, there had never
been such variations, it had always just gone up each time.
Or perhaps this is a known pattern when one is recurrent and it has possibly spread outside of the prostate ?
Here is the charting for the last year (again, not concerned here with actual psadt)
07/07/2016 - 2.0
08/16/2016 - 2.2
09/29/2016 - 2.5
11/06/2016 - 2.8
12/30/2016 - 2.9 - why did it not go up more here as per previous patterns ?
02/02/2017 - 2.8 - why did it go down here from 12/30 and again, not go up as per previous patterns ?
02/23/2017 - 3.5 - back where it would have been given previous trends
03/09/2017 - 3.5 - why did it not go up here as per previous patterns/trends ?
03/23/2017 - 3.3 - why did it go down here from 03/09 test and again, not go up as per previous patterns ?
05/04/2017 - 4.0 - back where it would have been given previous trends
05/25/2017 - 4.5 - it is where it would have been or a bit higher
06/14/2017 - 4.4 - again, its not only lower but not going up as per previous trends