Issue Description A malignant, rare, rapidly growing, highly
invasive variety of cancer. It is a blood-fed sarcoma; that is, blood
vessels grow directly into the tumor and it is typically filled with
blood. A frequent cause of death is the rupturing of this tumor,
causing the victim to rapidly bleed to death. Other Names HSA
Types Of Hemangiosarcoma Hemangiosarcoma can theoretically arise from
any tissue where there are blood vessels (which amounts to anywhere in
the body) but there are three classical locations which account for
Skin and Subcutaneous FormsThe skin form of hemangiosarcoma are the best
types to have as they are the most easily removed surgically (and thus
have the greatest potential for complete cure).
forms of hemangiosarcoma are classified as either "dermal" and
"subcutaneous". The true skin form looks like a rosy red or even black
growth on the skin. This form is associated with sun exposure and thus
tends to form on non-haired or sparsely haired skin (such as on the
abdomen) or on areas with white fur. Dogs with short white haired fur
(such as Dalmatians and pit bull terriers) are predisposed to the
development of this tumor. Approximately 1/3 of cases will spread
internally in the malignant way we usually associate with cancer so it
is important to remove such growths promptly.
The biopsy report will indicate whether or not the growth was
completely excised. If the tissue completely surrounding the growth is
normal, this indicates that the growth has been removed completely and
that it should not grow back.
If one wants to be absolutely positive that no tumor spread has yet
occurred, the following non-invasive (but not inexpensive) testing is
Chest radiographs - hemangiosarcoma tends to spread to the lungs.
Advanced tumor spread can be picked up with this simple test. (Spots
of tumor spread must be 3cm in diameter to be large enough to be
visible on a radiograph.)
Ultrasound of the belly - specifically the spleen. Even a small
splenic hemangiosarcoma should be detectable with ultrasound.
Ultrasound of the heart - even a small heart-based hemangiosarcoma
should be detectable with ultrasound.
Subcutaneous Or Hypodermal HemangiosarcomaThe overlying skin is often totally normal on
top of a subcutaneous hemangiosarcoma and often the surgeon is
surprised to find a dark red blood growth under the skin when the
tumor is removed.
Since up to 60% of hypodermal
hemangiosarcomas spread internally the above three tests to rule out
tumor spread are more important.
If no sign of tumor spread is found after chest radiographs have
been taken and ultrasound of the heart and belly are clear, prognosis
is substantially better than if secondary tumor is found; however,
additional treatment with chemotherapy is recommended if cure is the
Surgery alone has been associated with a 172 day (approximately 6
months) median survival time.
Splenic FormsThe spleen is a fairly deep-seated abdominal
organ which tends to go unnoticed unless it develops a growth of
unusual enlargement. Splenic growths have the unfortunate tendency to
break open and bleed profusely regardless of whether they are benign
or malignant. While a splenectomy (removal of the spleen certainly
ends the prospect of this type of life-threatening sudden bleed,
splenic hemangiosarcoma is still a rapidly spreading malignancy.
When a splenic mass is detected, it may not be possible to tell prior
to splenectomy whether or not the mass is malignant or not (though
certainly basic testing is performed in an attempt to determine this.)
25% of dogs with splenic Hemangiosarcoma also have a heart-based
Survival time with surgery alone is 19-65 days for splenic
Heart Base FormsLike the splenic hemangiosarcoma, the
heart-based hemangiosarcoma tends to exert its life-threatening
effects by bleeding.
The heart is enclosed in a sac called
the pericardium. When the hemangiosarcoma bleeds, the blood fills up
the pericardium until it is so full that the heart inside is under so
much pressure that it has no room to fill with the blood it has to
On chest radiographs the heart is spherical. In fact,
the actual heart is of normal shape but all that can be seen on the
radiograph is the large round heart shadow of the pericardium filled
to capacity with blood. Ultrasound is needed to truly see the
This condition, if allowed to progress, results
in an emergency circulating collapse called a "pericardial tamponade"
and can only be relieved by tapping the pericardium with a needle and
withdrawing the excess fluid.
63% of heart-based Hemangiosarcomas have evidence of tumor spread
at the time of their discovery.
Survival time for surgery alone (removing the pericardium and
snipping off the heart-based hemangiosarcoma) is approximately 4
Symptoms Visible bleeding, usually in the form of
nosebleeds, and signs associated with blood loss, such as tiring
easily, episodes of unexplained weakness, pale color to the mucous
membranes of the mouth and eyes, increased respiratory rates,
abdominal swelling and depression are the most common presenting signs
for patients with hemangiosarcoma. A few dogs just suddenly die with
no clinical signs having been noted by their families prior to death.
Diagnosis HSA is often suspected based on breed, age,
clinical signs, history and physical examination. Other tests that may
provide further support of this presumptive diagnosis include complete
blood count (CBC), serum chemistry profile, abdominocentesis (although
the presence of neoplastic cells is infrequent), coagulation profile,
three-view thoracic radiographs, abdominal radiographs, abdominal
ultrasound, echocardiogram and electrocardiography. These diagnostic
tests can also be used to clinically stage the severity of
disease.15,19 This system uses the size, site and character of the
primary tumor, and whether the cancer has spread to the regional lymph
nodes or undergone metastasis to distant sites to categorize the
disease into one of three clinical stages.19 However, there is no
proven difference in median survival times between different stages of
disease, so patients with HSA are not always fully staged.
Treatment Treatment and prognosis for Hemangiosarcoma
vary by location. Cutaneous Hemangiosarcoma is often curable with
surgery alone, provided the lesion is small and confined to the
dermis. Cutaneous Hemangiosarcoma often occur in areas of glabrous
skin on lightly pigmented dogs and arise as a result of sunlight
exposure. Lesions that are larger or deeper may be either primary or
metastatic lesions and warrant more aggressive treatment. Treatment of
splenic, atrial, or subcutaneous Hemangiosarcoma consists of surgical
excision of the primary tumor and adjuvant chemotherapy.
Prognosis The prognosis for patients with splenic HSA is
poor despite aggressive surgical, drug, or radiation therapy. Median
survival times for splenic HSA treated with surgery alone range from
19 days to 3 months; a one-year post-treatment survival rate for dogs
is less than 10%. Chemotherapy either with a single agent doxorubicin
protocol or with a combination drug protocol following splenectomy has
been reported to increase the median survival time to 140 to 202 days.
Addition of immunotherapy (L-MTP) reportedly increased survival to a
median of 273 days in one study.
The prognosis for cardiac
HSA also is poor despite therapeutic attempts. The reported mean
survival times of dogs with cardiac HSA that underwent surgical
therapy alone ranged from 3 to 5 months.
Cutaneous HSAs have a better prognosis than all other primary sites of
tumor origin. One study of surgically-treated cutaneous HSAs had a
median survival time of 780 days. In this same study, HSA that had
invaded the subcutaneous tissues and muscle had a median survival time
of 172 and 307 days, respectively. Chemotherapy may be warranted with
HSA that invades either the subcutaneous tissues or muscle.