Both publicly and privately there seems to again be a need for this
information due to confusion or lack of data so here are a few things
to help.  These are just a bit of info out there, but they form a good
foundation from which to learn more using resources such as
http://listserv.cuny.edu/archives/ferret-search.html,
http://fhl.sonic-weasel, and the crit refs at
http://www.ferretcongress.org
 
>The thread on this is pretty good, and both Sukie and Stephanie have
>very valid points.  The terminology of neoplasms can be confusing,
>and I'm sure even vets can be confused from time to time.
>
>The proper term for what you are talking about is neoplasm (or literally
>"new growth).  For one reason or another, a clone of cells begins to
>grow uninhibited by normal substances or mechanisms.  The word "tumor"
>may be technically correct, but it is actually non- specific - tumor is
>Latin for a swelling, but it could also be an abscess, or anything else
>that causes swelling - so I try to stay away from it.
>
>Now this neoplasm may be benign - without the ability for cells to
>detach into the bloodstream or lymph, move to another tissue, and set up
>shop - or malignant (where they can do this.) The process of microscopic
>piece of a tumor moving to another organ is called metastasis.
>
>Metastasis is the hallmark of malignancy.  The worst tumors have the
>propensity to go anywhere and start growing (like lymphoma).  However,
>we can recognize malignant tumors even before they metastasize, often
>by characteristic features seen under the microscope.
>
>Adrenal carcinomas (malignant adrenal tumors) are interesting neoplasms.
>Although they possess the ability to metastasize, only a small number do,
>and usually only late in the course of disease.  It is likely that they
>do metastasize a lot, but have trouble gaining a foothold in distant
>tissues, so it takes a long time and many attempts if they ever truly
>metastasize.
>
>Insulinomas are generally not malignant tumors as they only very rarely
>metastasize.  The presence of multiple tumors in the same organ over time
>is not metastasis.  We do not understand the mechanism behind the
>generation of these tumors, and when we do surgery to remove them, we
>really are only treating the end point of this process, without address
>the cause.  Thus it is really no surprise that the rate of recurrence is
>about 40% within 10 months.
>
>With kindest regards,
>Bruce Williams, DVM
[Posted in FML issue 4266]