How PSA testing added 16 years to my lifespan (so far)
ABOUT PSA
The Urologist in me finds it hard to believe that I have never written a post about PSA, although there has been so much hype about it for the past 20 years!
A usable -a very helpful- tool
This is one more case of a perfectly usable tool causing trouble for those folks who have never heard of, or don’t understand, the basic principles of due diligence and are too inconfident to use a fragile tool well.
Briefly, the Prostate Specific Antigen (PSA) test is a measure of a prostatic enzyme, PSA, whose physiologic purpose is to liquify the sperm “clot” which forms in the vault of the vagina following ejaculation, thus freeing the Spermatozoa to swim on up to the ovum.
The PSA enzyme is secreted into tiny tubules in the tissue of the prostate and is squeezed out into the ejaculate by spasmodic contraction of the microscopic muscles in the gland, at orgasm.
PSA does not enter the blood, normally
It does not enter the blood, except in tiny quantity, when the prostate is healthy and sexual activity is “normal” (I’ll leave the interpretation of that maltreated word, to the reader!).
However the walls ot the tubules into which the PSA enzyme is secreted are only one cell thick and ANY damage to the tubule wall can result in leakage into the interstitial fluid surrounding the tubule, whence it enters the blood.
Caveat
I must emphasise that in the case of the intra-prostatic tubules, “ANY DAMAGE” translates to “ANY DISTURBANCE”, because the walls are so thin…….. Any undue pressure in, or on, the prostatic tissue can produce such leakage.
UNBEKOMING, the substack blogger, is correct
So you are correct, Unbekoming, in saying (I quote from your post) “An elevated reading — typically above 4.0 ng/mL — does not mean you have cancer. It means your PSA is above an arbitrary threshold that was never scientifically validated. Enlarged prostates, infections, recent ejaculation, cycling, and even the digital rectal exam itself can elevate PSA. Three out of four men with elevated PSA do not have cancer” ………….
My “take” on PSA
Subscribe to continue reading
Subscribe to get access to the rest of this post and other subscriber-only content.