From:
Sukie Crandall
Date: 2001-08-20 15:49:00 UTC
Subject: Re: Re: adrenal and insulinoma malignancies ?? --
definitions from some dictionaries
At 8:59 AM +0000 8/20/01, Ferret-Health-list@yahoogroups.com wrote:
>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
Our server is having problems so I will just have to keep trying to
send this. Treat it as an supporting document to Bruce William's
excellent post above taken from FHL digest 348. I especially liked
his providing the direct translation of "tumor" as "swelling", and
his explanation that not all growths which can metastasize do so
readily.
These definitions are combined ones from medical, veterinary, and
biology dictionaries, but emphases are mine and i am willing to be
corrected if I blew it...
Important Note: some more recent dictionaries don't even include the
term cancer, and I have heard vets who won't use it due to the
widespread confusion out there, and even some vets who won't use
"tumor' due to too many assuming that any tumor is malignant.
Tumor: ANY abnormal mass resulting from the excessive multiplication
of cells; a swelling, especially that resulting from the growth of
new tissue; a neoplasm
cancer: Any MALIGNANT TUMOR; carcinoma; a carcinoma or sarcoma
malignant: pertaining to or denoting progressive growth of CERTAIN
tumors which if not checked by treatment spread to DISTANT sites,
terminating in death; a tendency to progress in virulence, cancer is
the best known example
benign: not malignant, as in CERTAIN TUMORS; not recurrent,
favorable for recovery
neoplasm: a tumor; any new growth, specifically one in which cell
multiplication is uncontrolled and progressive, neoplasms may be
benign or malignant
(Subsets from Saunders:
neoplasm, benign: a neoplasm having none of the characteristics of a
malignant neoplasm (see below), i.e.it grows SLOWLY, expands WITHOUT
METASTASIS, and USUALLY does not reoccur
neoplasm, malignant: a neoplasm with the characteristics of
anaplasia, invasiveness and metastasis
There are several other subsets of neoplasia in this dictionary.
metastasis: the transfer or disease from one organ or part to another
NOT DIRECTLY CONNECTED WITH IT
anaplasia: loss of differentiation of cells
Those who have the _Saunder's Comprehensive Veterinary Dictionary_
will find that this resource often provides details beyond these
bare-bones descriptions, (though certainly there also will be nuances
in practise that those of us who are not medical professionals simply
won't understand). It is a marvelous resource; I love it. If I had a
rating for refs around here it would be among the best buys. It's
better than any of my other medical dictionaries, even for sorting
through things too technical for me in the _PDR_ books on herbs and
on supplements that i have at home. Marvelous book: clearly written
and very inclusive; more than worth what it cost.