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May 28, 2019 – “Our dog was normal in the morning but was dead a few hours later – it was horrible!” Here at the Foundation we hear this far too often from our donors who’ve lost a dog to hemangiosarcoma, one of the deadliest types of canine cancer.

It seems impossible that a devastating cancer could arise quickly and rarely give an owner any clue that their dog is sick. Knowing more about how this cancer develops and learning to recognize the subtle signs of the disease is important for owners not only to spot a potential problem but also be prepared if hemangiosarcoma affects their dog.

Hemangiosarcomas arise from the cells lining blood vessels and develop in areas with a rich blood supply, including the heart and spleen. Because these tumors can suddenly rupture, causing massive bleeding, owners and veterinarians are forced to make difficult decisions within minutes of the diagnosis

Hemangiosarcoma most commonly affects:

  • Middle-aged to older dogs
  • German shepherds, golden retrievers and Labrador retrievers
  • Slightly more males than females (in some studies)

Unfortunately, there are no clinical signs (symptoms) that are classic for hemangiosarcoma. The most commonly reported signs include:

  • Intermittent lethargy or fatigue
  • Anorexia
  • Panting
  • Sudden collapse
  • Sudden death

Most pet owners are quick to act in cases of sudden collapse and time is of the essence in cases of hemangiosarcoma. These are true medical emergencies and many patients require immediate surgery to remove the bleeding mass (if possible) followed by supportive care to survive.

In the long term, the picture is bleak for most patients. The average survival time after surgery alone is a mere one to three months. Chemotherapy following surgery extends average survival times to four to six months of excellent quality of life. While some dogs can experience prolonged remissions of several years, the overall long-term prognosis remains poor for the majority of patients.

Morris Animal Foundation has been a leader in trying to find new, innovative therapies to treat hemangiosarcoma. We recognized that more work needed to be done on all aspects of hemangiosarcoma, from the basic mechanisms of tumor growth and spread to better treatments. Although we’re making steady progress we’ve got a long way to go to unlock the secrets of this terrible cancer and we need your help. Check out our website for ways you can help ensure that dogs live healthier, happier and longer lives!