>Adrenal gland tumors are so common (85% of all ferrets will eventually
>have it)
 
Interesting; that's more than twice the rate we tend to see in our
household if I am doing it right off the top of my head.
 
Okay, let's see: I'll work it out for the 20 years: Okay, I'm wrong.
Slightly more than half of our's have had adrenal growths.  Almost
all were benign though they of course needed surgery (except in the few
cases that were dying of something more serious and which had medical
approaches).  One had lympho there (A second probably had it go there but
it wasn't an early location for it in him but a very late one so in the
noise for calculations...) and one had an adenocarcinoma which was cured
by rapid surgery so she went on to have another 3 and 1/2 years of life.
(In rare cases adenocarcinoma will spread).  The only two who died of
those diseases were the ones with lymphoma.
 
We cover our ferrets at night and provide very dark areas for sleeping.
It hasn't impacted the number of benign adrenal neoplasia, but we don't
know if it might have made a difference in the number of malignant ones.
It may have or the difference may simply be coincidence.
 
Anyway, our experience differs from your's in rate.
 
I think that everyone likely is looking forward to the further editions
in Bruce William's series in "Ferrets" which will carry on his
explanations of what is and is not "cancer" and explain common growths.
For some of it will reduce writing, and for others it will reduce
confusion.
 
If I get a chance I'll dig up the very useful Golden Oldie, to help clear
up some of hte general confusion about "tumors", "cancer", etc.  that you
have also tackled in your post.
[Posted in FML issue 3859]