A form of cancer that originates in the
endothelium, which is the lining of blood
vessels and spleen. These tumors are highly
malignant and can be found almost anywhere in
the body. The spleen, pericardium and heart are
prone to be affected.
These tumors are most common in medium-sized
or large breeds of middle aged or older dogs but
can occur in any breed, including cross-breeds.
German Shepherds are reported to be more
susceptible to this form of cancer than most dog
breeds. The Golden Retriever also seems to have
a higher than normal incidence.
Quite often there is little warning of the
presence of these tumors before severe clinical
signs are seen. An estimate of the average time
from discovery of the tumor until death occurs
in affected dogs is six to eight weeks.
The most common initial symptoms include
visible bleeding, usually in the form of
nosebleeds, and signs associated with blood
loss, such as weakness, tiring easily, paleness
to the mucous membranes of the mouth and eyes,
increased respiratory rates, and abdominal
swelling. In some cases, dogs just suddenly die
with no clinical signs observed at all.
If a tumor in the spleen is found when it is
small, it may be possible to remove the spleen
or remove tumors found near the heart in order
to prolong the dog's life. However, most often
these tumors have spread by the time they are
identified. According to published papers, the
average survival time in dogs with
Hemangiosarcoma is only three to four months.
