Hemangiosarcoma in Dogs


Hemangiosarcoma is a type of malignant cancer typically found in middle-aged to older dogs. This form of cancer stems from the cells lining the blood vessels of various tissues of their body. Although the most common location of Hemangiosarcoma is the spleen, it can also occur in the heart, lungs, bones, muscles, kidneys, bladder, uterus and mouth. Tumors can actually grow anywhere there are blood vessels. It can also start in one spot and metastasize or spread to other organs. Hemangiosarcoma is a very aggressive form of cancer in dogs.

Because this cancer originates from the lining of the blood vessels, the tumors have a tendency to also invade the blood vessels. In time, most of these tumors rupture and bleed, which results in death from severe blood loss. The prognosis for dogs suffering from this type of cancer is very poor. Even with the best treatment, many dogs fail to live six months after diagnosis.

There are three types of canine hemangiosarcoma.

  • Dermal – This type of hemangiosarcoma is found on the skin.
  • Hypodermal – This type of hemangiosarcoma is found under the skin.
  • Visceral – The most common, this type of cancer is on the spleen, the heart and the lining of the heart. It is the most serious of the three. From 45% to 51% of the visceral hemangiosarcoma are found on the spleen.

Presentation in of Hemangiosarcoma in Dogs

Hemangiosarcoma tumors grow internally so there is very little warning of the disease until the symptoms become severe. Once the tumors begin invading the blood vessels, it can cause severe hemorrhaging into the abdominal or, sometimes, the chest (thoracic) cavity. Unfortunately, it isn’t until the disease has reached this point that symptoms start to present themselves. Symptoms may include the following:

  • Lethargy
  • Pale mucous membranes (eyes and mouth)
  • Abdominal swelling
  • Tiring very easily
  • Lack of appetite
  • Labored or rapid breathing
  • Weakness
  • Depression
  • Nosebleeds

The cause of this serious disease has not been determined. Dogs who are not diagnosed early enough can quickly suffer from breathing difficulties and weakness and may collapse and die instantly. Basic diagnostic testing is encouraged to help determine the progression of the disease and to identify the affected organs.

Breeds Commonly Affected

Although hemangiosarcoma can affect any breed of dog, the dogs most predisposed to this disease are German Shepherd, Labrador Retrievers and Golden Retrievers. For a reason no one really knows, male dogs seem to be more predisposed to getting hemangiosarcoma than female dogs.

Treatment Options

Before a veterinarian can make an accurate diagnosis and implement a treatment plan, the vet must perform a complete examination of the dog. This includes collecting the dog’s medical history and any history of the dog’s bloodline. The main purpose of the tests and examinations is to learn the extent of the hemangiosarcoma and to rule out other problems. In some cases, the tumor is already so large the vet can feel it during the routine exam. Examinations and tests used for the diagnosis include:

  • Physical examination
  • Blood biochemistry panel
  • Urinalysis
  • Complete blood count
  • Abdominal ultrasound
  • Chest and abdominal x-rays
  • Echocardiogram (ultrasound of the heart)
  • CT scans of the potentially affected organs
  • Clotting tests to determine if the dog’s blood can clot properly
  • Fecal exam
  • Chemistry test to evaluate sugar levels and organ functions
  • Blood parasite screening
  • Electrolyte tests to make sure dog isn’t dehydrated

Treatment for hemangiosarcoma can vary by a few different factors:

  • The size of the tumor
  • Location of tumor
  • If cancer has spread
  • Cost of treatment

Treatment may be surgically removing the tumor, chemotherapy, immunotherapy, radiotherapy and/or supportive care. Dogs who undergo surgery often face the risk of irregular heartbeats and need to undergo a second ECG to monitor the heartbeat and ensure it’s beating correctly.

The severity of the disease and the cost of treatment often make it very difficult for owners to give their dogs the treatment they need. Between examinations, surgeries, chemotherapy and post-operative care, medical bills can range from $500 to $3,000 per month.

When owners consider the cost, the dog’s poor long-term prognosis and the dog’s suffering, they often choose to not treat the dog. Many owners state that if it were only the cost and the dog would be cured, they would opt for treatment, but there is a high cost, plus little chance for survival. This is probably a reason why many dog owners are choosing to purchase pet insurance.


The overall prognosis for dogs suffering from hemangiosarcoma is guarded at best because it’s such an aggressive type of cancer. It has a high mortality rate and a median survival rate of only 3-6 months and many only living two months. The dog’s prognosis depends a lot on the part of the body that is affected the most.

Dogs with spleen-affected hemangiosarcoma have a very low prognosis rate even with the spleen removed because tumors in that area usually spread to the bloodstream and onto other organs like the heart or lungs. When combined with surgery and chemotherapy, the life span can extend six to eight months.

Sunlight-induced skim hemangiosarcoma is less severe and offers dogs a better survival rate if they have surgery and are kept out of extreme sun exposure. Unfortunately, the majority of hemangiosarcoma cases are of the serious kind. Although early detection and supportive care can enhance the dog’s quality of life, there is no method of prevention for hemangiosarcoma.

Despite there being no way to prevent hemangiosarcoma from developing in a dog, regular checkups with a qualified veterinarian can ensure there are no health issues going on and, if there are issues, they can be caught in the early stages.

Source: American College of Veterinary Internal Medicine