Prostate cancer thrives on testosterone. Sometimes doctors castrate
patients to reduce the testosterone that will drive a prostate cancer.
It seems harsh but it might be a case of would you rather be castrated
or die?
Alternate to castration they sometimes use testosterone repression
drugs to slow down hormones to castrate levels. All these attempts to
fight testosterone are very difficult as any pure drug will have
limited success. This happens because the body is a complex and
sophisticated feedback mechanism. It measures testosterone levels at
all times. So using a pure anti-androgen to reduce the effect of
testosterone essentially tells the feedback loop "hey, we need more
testosterone, we are not getting enough". The feedback loop then
determines the testicles to start producing more testosterone. So the
testicles start churning out nearly unlimited testosterone, and
eventually kind of overcome the effect of any "pure" anti-androgen, by
simply flooding the body with ever more testosterone.
This ongoing process can be overcome by things like GNRh agonists like
Lupron. They basically sneakily interrupt that whole feedback loop and
tell the body to shut down testosterone production. They essentially
"trick" it into thinking testosterone levels are too high in the body.
They can reduce testosterone to castrate levels basically as long as
you take them. Sometimes to reduce testosterone even further an
additional pure anti-a such as Casodex might be used on top of them.
