HEMANGIOSARCOMA
(This article is reprinted with
permission from the Spring 2009 isue of AKC CHF "Discoveries".)
The Van Andel Research Institution in Grand Rapids, MI needs additional
samples from Beagles diagnosed with hemangiosarcoma !
The CHCC (Canine Hereditary Cancer Consortium) is requesting samples from
beagles who have had hemangiosarcoma (usually splenic tumors). We simply need
three mls of whole blood in an EDTA (purple top) tube.
We are comparing the DNA of dogs who develop hemangiosarcoma to the DNA of dogs
who do not have the disease. These DNA studies are designed to help us develop
better treatments, earlier diagnostics and perhaps DNA tests to serve as another
tool in the breeders' toolbox.
The CHCC will pay for the shipping of samples from affected dogs.
Please contact Roe Froman, DVM, for more specific information regarding sample
submission. Thank you for your help!
Roe Froman, DVM
Senior Veterinary Research Scientist
Van Andel Institute
333 Bostwick Ave NE
Grand Rapids, MI 49503
616.234.5556
www.vai.org/helpingdogs
A
diagnosis of cancer is a frightening thing, whether you’re receiving
the
information about yourself, or a loved one. When that loved one is your
dog, it
can be all the more confusing, since they can’t tell you where it
hurts. A
recent poll of parent clubs determined that cancer in general is the
greatest
health concern for owners and breeders. That same poll listed Hemangiosarcoma as the second
greatest health
concern.
Hemangiosarcoma is a type of cancer
that begins
in the cells that line blood vessels. Tumors usually develop in the
spleen,
heart, or liver, although they can also been found in the skin, bone,
kidney,
brain, and other locations. Hemangiosarcoma is almost always malignant, and
tends todevelop slowly, but spread
rapidly, so that clinical
signs are often not noticeable until the tumors have metastasized and/or
ruptured, causing acute shock and
collapse. Clinical
signs of hemangiosarcoma include loss of
appetite,
arrhythmias, weight loss, weakness, lethargy, collapse, pale mucous
membranes,
and/or sudden death. The most severe signs are caused from acute blood
loss.
These can vary from an enlarged abdomen due to hemorrhage to bleeding
into the
lungs or the pleural space (outside the lungs) that compromises
breathing, to
bleeding into the heart sac that prevents the heart from beating
normally.
Metastasis is most commonly to the liver, stomach
lining,
lungs, or brain.
The
first line of treatment, whenever possible, is removal of the tumor
with the
affected organ, such as with a splenectomy.
The
standard of care includes chemotherapy as a follow-up to surgery.
Unfortunately, visceral hemangiosarcoma
(the type
that occurs in organs other than the skin) is most often fatal even
with
treatment, usually within weeks to months. However, approximately 10% to 15% of dogs
have
excellent response to treatment with durable remission and extended
survival.
We do not know why some tumors respond so well while most fail.
Hemangiosarcomas of the skin may be
successfully
treated if the tumor hasn’t metastasized to other internal organs. In
an effort
to turn the tide in the outcome of this horrible diagnosis, the AKC
Canine
Health Foundation has approved nearly $900,000 in grant funds to
support
research focused on three aspects of hemangiosarcoma.
These different approaches to solving the hemangiosarcoma
puzzle often overlap – which
allows for
a better chance of finding answers and letting our dogs live longer.
Investigators
began by researching the biological behavior of hemangiosarcoma.
This means that they looked at the tumors to see how they behaved under
different circumstances. Knowing how a tumor behaves can provide
insight into
which treatments are most effective, and can also provide valuable
information
for the development of novel therapies that can target that specific
tumor. Genetic
research of hemangiosarcoma looks for more
than a
“genetic cause” of cancer in a particular breed. Investigators also
search for
mutations in tumor suppressor genes (genes that prevent the division of
cells
or promote cell death) and/or oncogenes
(genes that
promote cell division and survival). These changes in genetic makeup
can
provide information on genetic risk factors (risk factors that have
nothing to
do with environmental triggers), early detection and diagnosis and effectiveness of
treatments.
Hopefully, this research will eventually lead to determining the
prognosis or
outcome of treatments, and potentially even treatments themselves.
Research
into new, more effective therapies for hemangiosarcoma
includes more than just treatment of the actual tumors. Scientists are
also
looking for ways to prevent tumors from developing in dogs with a
higher risk
(a vaccine of sorts). Novel treatments in development also include gene
therapies and immunotherapy. Gene therapy can be used when a mutation
is known
to exist. In most cases of genetic disease, the correct gene (without
the
mutation) is inserted into a cell or tissue to replace the mutant gene.
Corrective gene therapy is unlikely to succeed in cancer because every
cell in
the tumor would have to be provided with the gene in a stable manner.
So
scientists are instead working to develop approaches that deliver genes
to a
restricted number of cells as a way to activate the immune system or to
alter
the local tumor enviroment as a way to
control the
disease. Immunotherapy is a strategy based on the concept of altering the patient’s immune
system so
that it fights cancer cells as it would a bacteria or virus.
Targeted
therapies use special delivery systems to specifically target the tumor
cells
only, thereby preventing damage to surrounding healthy cells. Studies
have
already shown that there are certain breeds that are at higher risk for
developing hemangiosarcoma.
However, it can affect any dog, purebred or mixed breed alike.
Hemangiosarcoma is currently a fatal
disease. By
funding research, the AKC Canine Health Foundation hopes to provide
owners and
breeders with a means for earlier, more accurate diagnosis, more
effective
treatments, and ultimately prevention strategies. You can help by
participating
in clinical trials (visit the Veterinary Cancer Society website at www.vetcancersociety.org"
for a list
of active trials) and/or providing financial support to
the Canine Health Foundations efforts (visit www.akcchf.org to
make a secure online donation).
If
you would like additional information about the research the CHF is
funding on hemangiosarcoma,
visit our website at www.akcchf.org" and click on
“Research.”
VITAL STATISTICS FOR HEMANGIOSARCOMA
- CHF currently has three active grants approved at more than
$210,000.
- CHF has funded a total of eleven hemangiosarcoma grants for
nearly $900,000.
- In a poll of AKC Parent Clubs, hemangiosarcoma was listed as teh
#2 health concern.
HEALTH FACTS AND HEMANGIOSARCOMA
- Hemangiosarcoma affects dogs of all ages and breeds including
mixed breed dogs.
- Hemangiosarcoma is usually malignanat, and most often fatal, even
with treatment.
- Researchers are looking for better treatment options for
Hemangiosarcoma.