Hemangiosarcoma in Dogs

Hemangiosarcoma is a rare and dangerous cancer that affects dogs. Thankfully, early detection can greatly increase the chances of survival for your pup. There are three main types of hemangiosarcoma: cutaneous hemangiosarcoma, subcutaneous hemangiosarcoma, and hemangiosarcoma of the spleen. The one most often associated with dogs is splenic hemangiosarcoma. Since there’s no known cure for this disease, it’s essential to have your dog checked regularly if they are at risk for this condition and know what to look for in case you suspect that something might be wrong.

What is hemangiosarcoma?

Hemangiosarcoma is an aggressive and highly metastasizing cancer that affects the blood vessels. It can occur in any organ, but most commonly occurs in the spleen, liver, heart and lungs.

Hemangiosarcoma is second only to osteosarcoma as a cause of death from bone cancers among dogs with tumors. About 1% of all malignant tumors found in dogs are hemangiosarcomas.

There are several different types of hemangiosarcoma; there are subtypes based on location as well as size and shape (diameter). Lymph node enlargement may occur with some types of hemangiosarcoma, especially if it has spread from another site such as the spleen or liver into nearby lymph nodes (nodes that filter out toxins from your blood stream).

Types of hemangiosarcoma

Hemangiosarcoma is a rare form of cancer that affects the blood vessels. It occurs most often in dogs, though it can affect other animals as well. Hemangiosarcoma begins when there is an abnormal growth of tissue in your dog’s blood vessel walls. When this happens, the tumor will continue to grow and spread throughout your pet’s body until it becomes so large that it interferes with normal organ function or causes pain for your dog.

There are two main types of hemangiosarcomas: primary hemangiosarcoma and secondary hemangiosarcoma. Primary refers to tumors that originate from the inner lining of an artery while secondary refers to tumors which have originated elsewhere in the body but later metastasize (spread) into an artery wall.

Causes and risk factors

  • Age: Hemangiosarcoma is most common in middle-aged dogs, usually 5 to 10 years of age.
  • Breed: Several breeds have a higher risk of developing hemangiosarcoma compared with other breeds. These include German Shepherds and Golden Retrievers (also called Golden Labs). Other susceptible breeds include Boxers, Doberman Pinschers, Great Danes, Rottweilers and several others.
  • Gender: Male dogs are more likely to develop hemangiosarcoma than females (typically by 50%).
  • Family history: Although there isn’t strong evidence that the family history affects whether your dog will be at risk for developing hemangiosarcoma specifically, it’s important to note that certain cancers tend to run in families—namely breast cancer and melanoma. If your dog has developed any type of cancer before they had their first heat cycle or didn’t have any litters yet as an adult female then there is a greater chance that it could happen again when she goes into heat cycle or becomes pregnant later on if not already done so already; this includes breast cancer as well!

Diagnosis and treatment

The diagnosis of hemangiosarcoma is based on a physical exam and blood tests, which can reveal an abnormally high white blood cell count. Furthermore, if a tumor is present, the doctor may be able to feel it during a physical exam.

Because hemangiosarcoma is difficult to diagnose early on due to its similarities with other cancers, treatment usually begins after the cancer has spread beyond the organ where it began. Treatment options include surgery (which includes removing as much of the tumor as possible), chemotherapy and radiation therapy; however, these treatments are only effective in certain cases. For example:

  • Surgery is considered most effective for tumors that are located near an organ’s surface or in places where there are many small tumors rather than one large mass.
  • Chemotherapy is used when metastatic disease has developed (tumors have spread from their original sites).

Hemangiosarcoma can cause serious health problems in dogs.

Hemangiosarcoma is a common type of cancer that affects dogs. It is most commonly found in the spleen or liver, but it can also affect other organs such as the heart, kidneys and skin.

Hemangiosarcomas are not contagious; they do not spread from one dog to another through direct contact or by sharing food bowls, toys or beds. Instead, hemangiosarcomas develop in an individual dog because something has damaged its genes so that cells begin growing out of control (cancer).


Hemangiosarcoma is a very serious form of cancer that can have a very negative impact on your dog’s health. Although some dogs may live for months with this condition, others may die within days or weeks of the diagnosis. If you think your dog might be suffering from symptoms of hemangiosarcoma, it is important that you take them to the vet for an examination as soon as possible. Your vet will be able to diagnose the condition and recommend treatment options that can help improve your pet’s quality of life.