Leonberger Loses Fight with Hemangiosarcoma But Owners Battle On


One morning, Einstein, an 8 ½ year old Leonberger, failed to make his way upstairs in anticipation for his morning walk. Teresa Schlaffer instantly knew something was wrong. She went downstairs and found Einstein sleeping in the backyard. Even with encouragement from Ms. Schlaffer and her husband, Randy, Einstein barely moved.

The Schlaffers immediately loaded Einstein into the car and took him to their regular veterinarian. After a wait that seemed like an eternity, the veterinarian gave them the news: Einstein had a hemangiosarcoma in his heart. Upon the veterinarian’s suggestion the blood that had built up in Einstein’s pericardium was drained. After this procedure Einstein showed marked improvement. “Einstein was up, giving kisses to us and all the vet techs, and generally looking like his old self,” said Ms. Schlaffer. After several hours Einstein’s pericardium had not filled back up with blood. The vet scheduled an appointment for Einstein with a cardiologist the next day with. He also recommended making the next 16 hours count. The Schlaffers took their vet’s advice and spent the next 16 hours loving Einstein, lavishing him with extra-special attention and care.

At the cardiologist’s office the next morning the Schlaffers learned that Einstein’s pericardium was full of blood again. The cardiologist explained the surgical options. The average life expectancy post-op was 12 days, with the best case an additional two months.  “We asked if Einstein was in pain and the cardiologist indicated he was,” said Ms. Schlaffer. “We knew then that we couldn’t put Einstein through surgery so we made the difficult decision to let him go.”


The Schlaffers elected to have Einstein’s tumor biopsied which confirmed it was hemangiosarcoma. A year earlier The Schlaffers had donated a sample of Einstein’s DNA. Their hope is that this information will lead researchers closer to finding the genetic cause for this disease.

To further their commitment to Leonbergers and canine health, Ms. Schlaffer joined the Board of Directors of the Leonberger Health Foundation.  The Leonberger Health Foundation has supported the AKC Canine Health Foundation for many years, contributing to grants for oncology research, including those that specifically study hemangiosarcoma.  “I am carrying on Einstein’s fight,” said Schlaffer, “and the fight for all dogs that have succumbed to hemaniosarcoma, and the other devastating diseases that take our beloved canine companions from us.”

About Hemangiosarcoma

Sarcomas are cancerous tumors that arise from the cells of blood vessels, nerves, muscles, connective tissues or fat. Hemangiosarcoma is a particular type of sarcoma that arises from cells lining blood vessels – especially the smaller arteries and veins. Since hemangiosarcomas involve abnormal overgrowth of blood vessel tissues, they tend to bleed profusely when they are cut or disturbed. They are particularly fragile tumors that are prone to rupturing and causing internal bleeding that can be extremely dangerous - and often fatal - to the affected animal.

Unlike some of the other canine sarcomas, hemangiosarcomas are very invasive, fast-growing tumors that often migrate to the spleen, heart, liver, lungs, kidneys, muscle, lymph nodes or skin. Hemangiosarcoma is usually diagnosed using X-rays, ultrasound, CT scan, and tissue biopsies of suspicious masses. Chest X-rays are especially useful to determine whether the cancer has spread to the lungs.  Usually, by the time hemangiosarcoma is diagnosed, it has already metastasized, or spread, from its initial site to other places in the dog’s body.


While it is difficult to say with certainty how a dog with hemangiosarcoma is affected by its condition, reports from people with this disease, and observations of dogs, suggest that hemangiosarcoma usually causes a great deal of discomfort and pain, especially in the later stages. The exact symptoms will depend upon the site of the primary tumor (liver, spleen, heart, skin, bone, other), and where the cancer has spread.

Owners of dogs with hemangiosarcoma may notice a number of different symptoms, depending upon where the cancer started and the extent to which it has metastasized. Often, the initial signs of hemangiosarcoma are chalked up to old age, changes in weather, or alterations in the dog’s living environment. However, once the disease advances, the obvious physical deterioration associated with hemangiosarcoma usually develops very rapidly.

Initial symptoms may include:

Abdominal pain and distention; Lethargy (progressive); Depression (progressive); Weakness (progressive or intermittent, often with seemingly spontaneous recovery); Exercise intolerance (usually mild); Lack of appetite (inappetance; anorexia; usually starts mildly and progresses as the cancer spreads); Vomiting and diarrhea; Weight loss.

As the disease progresses, symptoms may include:

  • Visible lumps on the legs, head, face, ears, prepuce, muzzle, back, ribs, abdomen, flank area, belly or elsewhere
  • Abdominal pain and distention
  • Collapse (usually acute; happens without warning)
  • Shock
  • Difficulty breathing (dyspnea; respiratory distress; caused by internal bleeding from rupture of tumors that have spread to the lungs or chest cavity)
  • Abnormal heart rhythms (arrhythmias) and / or Elevated heart rate (tachycardia)
  • Weak pulses
  • Muffled heart sounds
  • Jugular distention
  • Enlarged liver (hepatomegaly) and / or enlarged spleen (splenomegaly)
  • Pale mucous membranes (pallor; especially of the gums)
  • Excessive formation and excretion of a large amount of urine (polyuria)
  • Excessive thirst and intake of water (polydipsia)
  • Blood clotting abnormalities
  • Lameness, limping
  • Swollen joints
  • Sudden death; usually results from uncontrollable bleeding caused by rupture of a hemangiosarcoma tumor, which causes the dog to bleed to death from internal hemorrhage


The actual causes of hemangiosarcoma, like the causes of most other types of cancer, are not well understood. Hemangiosarcomas can develop anywhere on the surface of a dog’s body, inside its internal organs, or within body cavities. Primary hemangiosarcomas tend to occur most frequently in the skin, heart, spleen, liver, and bone. Hemangiosarcoma of the heart is one of the most common cardiac cancers in companion dogs. Certain breeds such as Boxers, Doberman Pinschers, English Setters, German Shepherds, Golden Retrievers, and Labrador Retrievers have shown a more prevalent risk, suggesting a genetic component to its cause, however, all dogs are at risk for developing hemangiosarcoma.

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