The following article is from the Jan/Feb 1994 issue of "Off The Paw", the
Official Newsletter of the Greater Chicago Ferret Association. [IFNS]
 
MAST CELL TUMORS
by Dr. Susan A. Brown, DVM - Midwest Bird & Exotic Animal Hospital
 
Mast cell tumors are seen in a variety of species of animals including dogs,
cats, cattle, horses, and man.  Mast cell tumors go under a number of names,
all meaning the same condition:  mastocytoma, mastocytosis, mast cell
sarcoma.  Mast cells are a type of cell that are associated with the immune
system and are found throughout the body in a variety of areas such as bone
marrow, lymphoid organs, connective tissue and under the lining (mucosa) of
the respiratory and gastrointestinal tract.  Mast cells are active
participants in immune reactions against foreign substances.  Within the cell
body are granules which contain chemical substances such as histamine,
serotonin, prostaglandins and others that create local inflammation which
helps to destroy the foreign substance that has entered the body.
 
The cause of mast cells growing abnormally and creating a tumor is unknown in
the ferret.  It is an extremely common skin cancer in ferrets particularly in
those animals three years of age and older.  The appearance is usually that
of a raised button-like lesion that is flat on top.  The size may range from
as little as 1/8 inch to over 1 inch.  A few cases show as a diffuse raised
red area that may be larger than one inch in diameter.  The size may even
change, and some small tumors seem to disappear temporarily.  Because of the
release of histamine from these cells, which can cause intense itching, some
tumors have an ulcerated or raw appearance to their surfaces.
Mast cell tumors can be found anywhere on the ferret's body but most
typically on the trunk.  They are also found on the toes, eyelids and tail.
Athough they are usually benign (meaning that they do not spread to other
organs in the body) in the ferret, on occasion we have seen a malignant form
that metastasizes to the spleen, liver or lung.  The tumors usually occur in
groups of one to three on the body.
 The treatment is to remove the tumor or tumors surgically as soon as possible
to prevent the possibility of metastasis.  Surgery is fastest when the tumor
is small.  We use electrosurgery which has proven to be a fast and effective
way  to remove them.  We recommend that skin tumors be sent to a pathologist,
because even though it may look like a mast cell tumor, we cannot know for
sure until it is examined microscopically.  Microscopic examination will also
give us a clue as to whether the tumor is benign or malignant, and what
further treatment might be necessary for your pet.  I have not yet seen a
mast cell tumor return in the place where it was removed.
 
I recommend as a general rule that lumps and bumps on ferrets be removed
promptly because they are so prone to cancers of all types, and why take a
chance!  I recommend taking you buddies to the veterinarian at least every 6
months after the age of 3 to keep ahead of all the possible problems that
they may have.
 
As always.......a hug and a kiss for the critters until next time!
 
 
[Posted in FML issue 0672]