Free PSA test is what caught my cancer and should be considered by anyone
before a biosy. My total PSA went from 2.0 to 3.1 in 16 months and the
free PSA was 14%. Then a biopsy showed 4 of 10 cores positive. My doctor
would not have recommended a biopsy if the free PSA was greater than 25%.

I also learned that not all labs can do a free PSA, if the total PSA is
below 4.0. A prior lab showed my PSA at 3.4 and NORMAL, and stated they
can't do a free PSA below 4.0, as my doctor had requested. It is too bad
PSA velocity and free PSA are not more publicized. Sad.

Just to further complicate matters, it should be borne in mind that fPSA is
a *component* of PSA -- a percentage. Therefore, it cannot be considered
apart from "regular" PSA. Strum, in _A Primer on Prostate Cancer_
vol. 1, page 39, agrees with Walsh, "Lower free PSA percentages, in
multiple studies, have been shown to correlate with greater risk for
non-organ-confined PC."

My understanding of the above is that, if fPSA is >15% (here, he agrees
with Walsh), Strum clearly and unequivocally states that there is a risk
that the PCa has  already escaped the gland. This is substantially
different from being a reliable marker for *the mere existence* of PCa.

Reading this portion of the book leads me to conclude that Strum believes
that PSADT (PSA doubling time) and PSAV (PSA velocity) are, as he puts it,
"...clues to significant biological changes that indicate malignancy"
and of greater importance than fPSA. The latter is, "...a useful tool to
evaluate patients with pretreatment PSAs in the 4 to 10 range and even at
lower total PSA levels ranging from 2.51to 4.0 ng/mL."

I wouldn't ignore it, but by the same token wouldn't put a great deal of
confidence in it as a single marker, especially when the patient has
already been diagnosed with PCa.

Does Walsh give a citation for this? I'd like to read it.

Respectfully disagree. What it can do is give the patient one clue as to
whether the PCa has escaped the gland. It is necessary to bear in mind that,
as above noted, fPSA is *a component* of PSA, which in the main consists
of complexed PSA (associated with PCa) and free PSA (Strum, p. 37).

Fundamentally, it appears to me that Walsh errs by considering fPSA in a
vacuum, not as one piece of clinical evidence in the investigation of the
biology of the tumor under consideration.

There, I've disagreed with The Great Walsh, and will probably be
criticized for it. In my defense, I'll point out that it is Strum who
disagrees.

Fundamentally, it seems to me that fPSA has recently -- at least on this
NG -- been assigned an importance that is greater than it should be. I
think that it should be considered along with other markers, not standing
alone.

BTW, while checking references, I found the following item of interest on
page 38 of Strum's book: "...prostatitis can result in low free PSA
percentages that make laboratory distinction from PC treacherous." Hmmm.

Regards,

Steve J

"If you know the enemy and know yourself, you need not fear the result
of a hundred battles. If you know yourself but not the enemy, for every
victory gained you will also suffer a defeat. If you know neither the
enemy nor yourself, you will succumb in every battle."
--Sun Tzu, "The Art of War"