From: kabrahamsen@comcast.net (KenA)
I've also wondered how much should I be concerned that in the last 3
months my PSA has gone from undetectable to 0.04.
As per: http://www.phoenix5.org/Basics/psaPostSurgery.html "On a
technical level, in the laboratory, Chan trusts the sensitivity of
assays down to 0. 1, or slightly less than that. ''You cannot reliably
detect such a small amount as 0.01,'' he explains. ''From day to day,
the results could vary -- it could be 0.03, or maybe even 0.05'' -- and
these ''analytical'' variations may not mean a thing. ''It's important
that we don't assume anything or take action on a very low level of PSA.
In routine practice, because of these analytical variations from day to
day, if it's less than 0. 1, we assume it's the same as nondetectable,
or zero.''
I know it's currently still quite low, but for me it's still a
surprising jump in only 3 months.
I feel like it's going to be a nerve-racking next 3-6 months for the
follow-up PSA tests to see if there's a PSA velocity that's high. Ken!
==================================

hi ken - your last statement says it all and it is going to haunt you
for the rest of your life when you get your psa test ran.   i call it
the 'psa jitters'.  happens about a couple of weeks before the test is
due and then when you get your resutls,  you breathe a sigh of relief
and then, the anxiousness goes away until the next time.

while there is truth in the 'white noise' of the psa, it seems that the
opinions are as different as there are people on what the bottom cutoff
should be so as to rule out false positives.

~ curtis

knowledge is power - growing old is mandatory - growing wise is optional    
"Many more men die with prostate cancer than of it. Growing old is
invariably fatal. Prostate cancer is only sometimes so."
http://community.webtv.net/PALMER_ENT/doc

To me, it seems fairly obvious that the smaller the amount (in this case
4/100ths of a nanogram) the less accurate the measurement relative to the
amount.  Imagine a gallon of swirling water with sand in it and you have a
cup that can reliably capture all the sand in the swath you take with the
cup.  Can you rely on better on the sample you take out of the water with
lots of sand or the one with a little.  In either case, I'd wager that if
you did it over and over, you'd find that the amounts differ, but with
respect to the total, the amount will differ less with the water with the
greater amount of sand.

I imagine in fact that the amount of difference is the same.  When I had a
0.75, it might have actually be a 0.751 one time or a 0.754 another.  Now
that I am a 0.04, a new PSA of 0,01 would look great to me, but would
probably be of little significance.