Bladder, Brain, Head & Neck, Hemangiosarcoma, Lymphoma, Mammary, Mast Cell Tumor, Osteosarcoma, Skin, Testicular Cancers
Antiangiogenesis, Chemotherapy, Clinical Trials, Radiation, Surgery, Complementary & Alternative Treatments
Afterlife
Hemangiosarcoma is an aggressive, malignant tumor of blood vessel cells. With the exception of the skin form of hemangiosarcoma, a diagnosis of
hemangiosarcoma is serious.  Because these tumors start in blood vessels, they are frequently filled with blood and when a blood-filled tumor ruptures,
it can cause problems with internal or external bleeding.

Hemangiosarcoma can theoretically arise from any tissue where there are blood vessels, which is essentially anywhere in the body, but usually appear
in the skin, soft tissue, spleen or liver with the most common site being the spleen.  They are highly metastatic and will frequently spread to the brain,
but also to the lungs, spleen, heart, kidneys, skeletal muscle and bone..  They are typically classified as dermal, subcutaneous or hypodermal, and
visceral.

Dermal Hemangiosarcoma
The skin form of hemangiosarcoma are the most easily removed surgically and have the greatest potential for complete cure. The  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 usually associate with cancer so it is important to
remove such growths promptly.  This form of menagiosarcoma is covered more broadly in the
Skin Cancer section of this website.
Definition
Hemangiosarcoma
The dermal form of Hemangiosarcoma is associated with sun exposure.  It is uncertain what the causes are for the other forms of this disease, but in humans exposure to
certain chemicals, such as vinyl chloride has been implicated.  Because of the increased incidence in several breeds, a genetic link appears to be one of several likely
causes. Hemangiosarcoma is rarely found in humans, so less research has been done, and the amount of information about the cause of this tumor is somewhat limited.
Causes
Hemangiosarcoma is more common in dogs than in any other species. It usually occurs in middle-aged to older dogs 6 to 13 years of age, although it has been seen in
dogs less than one year of age.  It tends to develop in mid to large size breeds and especially German shepherds, golden retrievers, boxers, and English setters.

The most common primary location of this cancer in dogs is the spleen. Other primary locations include the heart, liver, skin, and bone; however, it can start in any location
where blood vessels are present. These tumors usually spread to the lungs, liver, spleen and heart.
Risk Factors
Symptoms
Because hemangiosarcoma tumors most often in develop in internal organs, frequently, there are few or no  obvious symptoms before the onset of  severe clinical signs of
disease.  Signs of this disease are usually the result of the tumor rupturing, which causes bleeding. This may occur without any warning, and the symptoms will depend
upon where the tumor is located.  The most common symptom will be a lump under the skin, visible bleeding, sometimes in the form of nosebleeds, tiring easily, episodes of
unexplained weakness, pale color in the gums, difficulty breathing, abdominal swelling, seizures, abnormal heart rhythms, collapse, and depression.

When the tumor is located in the spleen or liver, the clinical signs are usually due to rupture of the tumor and subsequent bleeding into the abdomen. This causes anemia,
weakness and if the bleeding is severe, collapse. The gums may appear to be pale or white.  In relative few dogs, the diagnosis is made before the tumor ruptures.
When the  tumor is located in the heart, it can cause symptoms, such as weakness, collapse, difficulty breathing, exercise intolerance and fluid build-up in the abdomen.
This is usually due to the development of fluid around the heart, called pericardial effusion. The pericardium is a thin sack that surrounds the heart and  with
hemangiosarcoma, the pericardium fills up with blood due to rupture of the tumor.

When the tumor occurs in the skin, a mass or lump can usually be felt in or under the skin. The mass may become ulcerated and bleed. When the tumor occurs in a bone,
it can cause pain and discomfort. In some locations, such as a rib, the tumor can be felt as a firm swelling in the bone.
Diagnosis
Treatment
The treatment for hemangiosarcoma depends upon the location of the tumor. Treatment is more successful when this cancer occurs on the skin than when it is found in an
internal organ.  Most dermal hemangiosarcomas can be successfully treated and cured by surgical removal of the tumor.  Chemotherapy is often used in addition to
surgical excision if the veterinarian was not able to remove the entire tumor or it has penetrated into the subcutaneous tissue or muscles below the skin.  Radiation therapy
is also used to treat dermal hemangiosarcoma.

The visceral forms of this disease require more aggressive treatment, and even then, the treatment will not likely be curative.  If a tumor is identified when it is small, it may
be possible to remove the spleen if the tumor is there or to remove tumors found near the heart and prolong the dog’s life. A pericardial tap may be required to treat the
build up of fluid around the heart or the pericardial sac may be removed.  Surgery alone will not make much difference because these are highly malignant tumors and
most have spread by the time they have been diagnosed.  For this reason, combining surgery with chemotherapy is the standard treatment.  Many chemotherapy protocols
exist which may include the following drugs: cyclophosphamide, vincristine, doxorubicin, and cytoxan.   The use of radiation has not been proven to be useful in fighting this
disease at this time.

Treatment for the bleeding disorders and aggressive supportive care also prolong the life of patients with hemangiosarcoma.
Prognosis
Hemangiosarcoma is rarely curable and long-term prognosis for dogs with hemangiosarcoma is poor.  Dogs with internal organ involvement who are treated with surgery
alone live an average of only 2 months. Dogs who do not have identifiable metastasis at the time of surgery and who are treated with chemotherapy live a median of 6 to
10 months.  Some dogs with demonstrable metastasis may also respond to chemotherapy, providing a prolonged quality of life compared with dogs that are not treated at
all. Dogs with this type of cancer located in the subcutaneous tissues (just under the skin) live a median of about 6 months with surgery alone.

Studies have shown that surgery to remove the spleen (splenectomy), offers a median survival time of 19-83 days.  Dogs with a primary tumor of the spleen that has not
ruptured, has a better prognosis.  However, if the spleen has ruptured before it can be removed, the prognosis is poorer.  The combination of splenectomy and
chemotherapy can increase survival time but fewer than 10% of dogs survive a more than one year.

The blood disorder that most commonly accompanies the presence of hemangiosarcoma tumors is disseminated intravascular coagulation (DIC). This is blood clotting that
is occurring inappropriately inside the blood vessels.  It uses up all of the blood clotting elements rapidly and dogs with this condition usually have platelet deficiencies,
increased blood clotting times, decrease in fibrin content in the blood and an increase in fibrin degradation products (FDPs).  This may be the cause of death in many dogs
affected with hemangiosarcoma.
examination of the dog. This may include looking at the mucous membranes for signs of anemia (pale gums), aspirating fluid from the abdomen, drawing blood to see if it
urinalysis and radiographs (x-rays) of the chest and abdomen to determine the extent of organ involvement and whether metastasis is present.  An ECG plus cardiac and
clots form, and taking a history of the dog’s recent behavior and activities.  Further diagnostic work-up will most likely include a complete blood count, chemistry panel,
urinalysis and radiographs (x-rays) of the chest and abdomen to determine the extent of organ involvement and whether metastasis is present.  An ECG plus cardiac and
multiple tumors, the primary tumor site may be difficult to determine, and there is great risk of severe hemorrhage.abdominal ultrasound may be ordered if available.
Definitive diagnosis is accomplished by biopsy or removal of the tumor. This can be challenging because there may be multiple tumors, the primary tumor site may be
difficult to determine, and there is great risk of severe hemorrhage.
Subcutaneous (hypedermal) Hemangiosarcoma
The overlying skin of a subcutaneous hemangiosarcoma is often completely normal.  However below the skin is a dark red blood growth.  
Up to  60% of hypodermal hemangiosarcomas spread internally

Visceral Hemangiosarcoma - spleen
The spleen is a large abdominal organ which while not essential for life, serves an important role to the  blood and lymph functions.  
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) 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 although
testing will most likely be performed to attempt to determine this.  It has been estimated that 25% of dogs with splenic Hemangiosarcoma
also have a heart-based Hemangiosarcoma.

Visceral Hemangiosarcoma - heart
Similar to splenic hemangiosarcoma, heart-based hemangiosarcoma tends to be life-threatening from the  effects of 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 pump.  This is called pericardial effusion and
must be treated before an emergent situation occurs.
Information and
Inspiration when you
need it most
 
Read Ginger’s amazing
story of hope with
hemangiosarcoma or
Sumner and his foundation
and support group.
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