I'm confused. No one has explained to me what the
difference is between a growth, a tumor, or a cancer. My
dog has these bumps of different sizes under her skin but my vet
says not to work, they're just fat deposits.
When is a lump a cancer? Is a
mass a cancer? Are all tumors cancerous?
Oh, yes... how can you tell when a
lump or whatever needs to be surgically removed?
A histiocytoma... not a tumor
A biopsy procedure entails obtaining a small tissue sample from
a larger mass (not totally removing the mass) for microscopic
evaluation by a pathologist. Biopsies can be taken via
needle penetration of the mass or by scalpel excision or even by
a pinch or punch technique.
An impression smear utilizes a glass microscope slide that is
pressed onto an open lesion which imparts cells onto the slide.
These cells are then stained and analyzed.
You have some excellent questions
and we'll try to simplify, keeping in mind that in medicine
there are often grey areas of knowledge as we strive to clarify
information as black or white. For example a group of
cells in the skin may appear under microscopic examination to be
nearly normal...or not quite abnormal... or precancerous... or
display early changes from normal. And that's the best we
can do for now in some situations.
When does a lump need to be
1.) When there is evidence from a biopsy that the lump is
a type of cancer that could continue to grow or spread.
2.) When its presence creates a comfort, movement,
infection or cosmetic problem.
3.) When it is a cyst filled with dead skin or fluid
and poses a threat of infection or significant tissue damage or
disfiguration. An example would be an enlarging sebaceous
cyst on an eyelid margin.
Look at the definitions in the
column to the right. Each term (word) could have
several descriptions of a definition, plus... there are several
Specialist in Veterinary Pathology needs to look st the cells
before a definitive diagnosis can be
made regarding any tumor. Your veterinarian may elect to
make an informed presumptive diagnosis, but a definitive
diagnosis rests with the pathology specialist after looking at microscopic
specimens of the tissue. Based upon
established protocols, cells will fall into certain
classifications ranging from normal through highly malignant.
By taking a sample of the lump or bump, called
doing a biopsy, your
veterinarian will be best able to tell you what a lump is and
what, if anything, needs to be done.
dermatologist told me "The only way we know
if we need to do a biopsy is to do a biopsy".
Let's look over a few short
A lump is is an abnormal enlargement of tissue
A growth is tissue that has enlarged by excess cell
reproduction. To find out what the growth is, a tissue
sample (biopsy) needs microscopic analysis by a veterinary
pathologist. So the term "growth" is very general.
A mass is
A tumor is
A cancer is a.)
Benign refers to a tissue mass that stays confined to the
immediate area, does not metastasize, and may or may no do harm
depending upon where it originates and how large it becomes.
Malignant means rapidly growing, invasive and capable of
spreading cancerous cells through the blood or lymph to other
areas of the body.
A tumor characterized