Canine Hemangiosarcoma

At Animal Cancer Care Clinic (ACCC), we understand that receiving a diagnosis of hemangiosarcoma, a serious and aggressive cancer of blood vessel lining cells, in your beloved dog can be a time of great worry. Please know that our dedicated and compassionate team is here to support you and your furry companion every step of the way. While hemangiosarcoma is a challenging disease, we have advanced diagnostic and treatment options aimed at managing the condition, addressing potential complications, and maximizing your dog’s quality of life for the time we have.

What is Hemangiosarcoma?

Hemangiosarcoma is a malignant tumor that originates from the endothelial cells, which line the blood vessels. It is a highly aggressive cancer known for its rapid growth and its tendency to spread (metastasize) early to other parts of the body. In dogs, hemangiosarcoma most commonly occurs in three primary locations:

• Splenic Hemangiosarcoma: The spleen is the most common primary site for this tumor. Often, these tumors can grow large and may rupture, leading to life-threatening internal bleeding.
• Cardiac Hemangiosarcoma: This form arises from the heart, most often from the right atrium (upper chamber). It can cause fluid accumulation around the heart (pericardial effusion), leading to cardiac tamponade (compression of the heart) and sudden collapse.
• Cutaneous (Skin) and Subcutaneous Hemangiosarcoma: This form occurs in the skin or tissues just beneath the skin. While it can be locally aggressive, it generally has a lower metastatic rate compared to the splenic and cardiac forms.

Less commonly, hemangiosarcoma can occur in other locations such as the liver, lungs, kidneys, and bone marrow.

What Causes Hemangiosarcoma in Dogs?

The exact cause of hemangiosarcoma in dogs is not fully understood in most cases. However, some factors are believed to increase the risk:

• Genetics: Certain breeds, particularly large and deep-chested breeds like German Shepherds, Golden Retrievers, Labrador Retrievers, Boxers, Portuguese Water Dogs, and Scottish Terriers, have a higher incidence of hemangiosarcoma, suggesting a genetic predisposition.
• Age: Hemangiosarcoma is more common in older dogs, typically between 6 and 13 years of age.
• Chronic Ultraviolet (UV) Light Exposure: Cutaneous (skin surface) hemangiosarcoma may be linked to chronic sun exposure in areas with thin or light-colored hair.

It’s important to reassure you that hemangiosarcoma is not contagious to other pets or humans.

Signs and Symptoms of Hemangiosarcoma:

The signs and symptoms of hemangiosarcoma in dogs can be vague and often depend on the primary location of the tumor and whether it has ruptured or metastasized:

• Splenic Hemangiosarcoma:
  • Weakness, Lethargy: Due to anemia from internal bleeding.
  • Pale Gums: Another sign of anemia.
  • Abdominal Distension: Due to blood accumulation in the abdomen.
  • Sudden Collapse: If the tumor ruptures and causes severe internal bleeding.
  • Decreased Appetite
• Cardiac Hemangiosarcoma:
  • Weakness, Lethargy: Due to reduced cardiac output.
  • Exercise Intolerance: Difficulty breathing or tiring easily.
  • Coughing
  • Abdominal Distension (Ascites): Fluid buildup in the abdomen due to heart failure.
  • Muffled Heart Sounds: Due to pericardial effusion.
  • Sudden Collapse: Due to cardiac tamponade or arrhythmias.
• Cutaneous and Subcutaneous Hemangiosarcoma:
  • Visible Lump or Mass on the Skin: These can vary in size and may appear dark red, black, or bluish. They may bleed easily if traumatized.
  • Swelling or Bruising: Around the tumor site.

Due to the often vague and acute nature of the signs, prompt veterinary attention is crucial if you notice any of these symptoms, especially sudden weakness or collapse.

How is Hemangiosarcoma Diagnosed?

Diagnosing hemangiosarcoma at typically involves a combination of the following:

• Physical Examination: A veterinarian will perform a thorough physical examination, paying close attention to any palpable masses, abdominal distension, or signs of cardiac compromise.
• Blood Work: A complete blood count (CBC) may reveal anemia (low red blood cell count) and changes in platelet counts. A serum chemistry panel can help assess overall organ function.
• Coagulation Tests: These tests evaluate the blood’s ability to clot, which can be important in cases of bleeding tumors.
• Abdominal Ultrasound: This imaging technique is crucial for visualizing the spleen, liver, and other abdominal organs and identifying masses or evidence of bleeding.
• Echocardiogram (Cardiac Ultrasound): If cardiac hemangiosarcoma is suspected, an echocardiogram is necessary to visualize the heart and detect masses or pericardial effusion.
• Thoracic Radiographs (X-rays) or CT Scan of the Chest: To check for metastasis to the lungs, which is a common site of spread. A CT scan is more sensitive for detecting small lung nodules.
• Fine Needle Aspirate (FNA) or Biopsy: FNA of a skin mass may provide a preliminary diagnosis. However, due to the fragile nature of these tumors and the risk of bleeding, a surgical biopsy is often preferred for a definitive diagnosis and to assess the tumor’s characteristics. Splenic or cardiac masses are often not biopsied prior to surgery due to the risk of hemorrhage or complications, but can be in certain cases.
• Cytology of Abdominal or Pericardial Fluid: If there is fluid accumulation in the abdomen or around the heart, a sample may be collected and analyzed for the presence of cancerous cells.

Treatment Options for Canine Hemangiosarcoma:

At Animal Cancer Care Clinic, our treatment approach for hemangiosarcoma focuses on addressing the primary tumor, managing bleeding, and slowing the spread of metastasis to improve your dog’s quality of life and, hopefully, extend survival time. Treatment options may include:

• Surgery:
  • Splenectomy (Surgical Removal of the Spleen): This is the standard treatment for splenic hemangiosarcoma. While surgery can address the immediate risk of rupture and bleeding, it is important to understand that microscopic metastasis is often already present at the time of diagnosis.
  • Pericardial Effusion Drainage (Pericardiocentesis): For cardiac hemangiosarcoma causing pericardial effusion, draining the fluid around the heart can provide temporary relief and improve cardiac function. However, the effusion often recurs. Surgical removal of cardiac hemangiosarcoma is challenging and not always feasible.
  • Surgical Excision of Cutaneous/Subcutaneous Tumors: Complete surgical removal with wide margins is the primary treatment for localized cutaneous and subcutaneous hemangiosarcoma. Cryotherapy is treatment that involves freezing the tumor with liquid nitrogen and may be an option for hemangiosarcoma on the skin surface.
• Chemotherapy: Due to the high metastatic rate of hemangiosarcoma, chemotherapy is a recommended component of the treatment plan following surgery for splenic and cardiac forms. It aims to target and kill microscopic cancer cells that may have already spread. Various chemotherapy protocols are available, and our veterinary oncologists at ACCC will develop a personalized plan for your dog. Chemotherapy may also be used for non-resectable tumors or in cases with known metastasis.
• Radiation Therapy: Radiation therapy may be used for cutaneous or subcutaneous hemangiosarcoma that cannot be completely removed surgically or for palliative treatment of localized disease.
• Anti-angiogenic Medications: These drugs aim to inhibit the growth of new blood vessels that tumors need to grow and spread. Some anti-angiogenic medications are being investigated for the treatment of hemangiosarcoma.
• Supportive Care: Supportive care, including blood transfusions in cases of severe anemia and medications to manage pain or complications, is essential.

What to Expect During and After Treatment:

If your dog undergoes treatment for hemangiosarcoma at ACCC, you can expect:

• Close Monitoring: Our team will closely monitor your dog’s recovery after surgery and their response to chemotherapy, including regular physical examinations and blood work.
• Post-Surgical Care: Following surgery, we will provide detailed instructions for post-operative care and pain management.
• Management of Potential Side Effects: We will proactively manage any potential side effects associated with chemotherapy.
• Regular Follow-Up Appointments: These appointments will involve physical examinations and potentially repeat imaging studies (chest radiographs, abdominal ultrasound, echocardiogram) to monitor for metastasis or recurrence.

Prognosis for Canine Hemangiosarcoma:

The prognosis for dogs with hemangiosarcoma is generally guarded due to its aggressive nature and high metastatic rate. However, treatment can often provide valuable quality time:

• Splenic Hemangiosarcoma: With splenectomy alone, the median survival time is typically 1-3 months. With splenectomy followed by chemotherapy, the median survival time can often be extended to 6-9 months.
• Cardiac Hemangiosarcoma: The prognosis for cardiac hemangiosarcoma is typically poorer, with median survival times of 1-3 months even with pericardiocentesis and chemotherapy.
• Cutaneous/Subcutaneous Hemangiosarcoma: The prognosis for completely removed cutaneous or subcutaneous hemangiosarcoma is generally better, with longer survival times and a lower metastatic rate. Some dogs can be cured. However, more aggressive forms can occur.

We will discuss the potential prognosis for your dog based on the location of the tumor, the stage of the disease, and the chosen treatment plan at ACCC. Our goal is to provide realistic expectations while focusing on maximizing their comfort and quality of life for the time we have.

Coping with a Hemangiosarcoma Diagnosis:

Receiving a diagnosis of hemangiosarcoma for your dog is incredibly difficult, and we understand the emotional impact this has on you and your family. Please know that the team at Animal Cancer Care Clinic is here to offer not only the best possible medical care for your dog but also compassionate support for you during this challenging time.

We encourage you to ask us any questions you have and to share your feelings and concerns openly. We want you to feel informed and supported as you make important decisions about your dog’s care and how to best spend your time together.

Our commitment is to work with you to develop a treatment plan that is tailored to your dog’s needs and your wishes, while always prioritizing their comfort, quality of life, and your shared bond.

Questions to Ask Your Veterinarian at ACCC:

To help you better understand your dog’s condition and the treatment options available at Animal Cancer Care Clinic, here are some questions you may find helpful to ask us:

• What is the primary location of the hemangiosarcoma in my dog?
• Has the cancer spread to other parts of the body? If so, where?
• What are the treatment options available for my dog’s hemangiosarcoma?
• What are the goals of each treatment option (e.g., managing bleeding, slowing spread, extending survival, improving quality of life)?
• What are the potential side effects of the recommended treatment plan? How will these be managed?
• What is the expected prognosis for my dog with the recommended treatment?
• How will my dog’s comfort and quality of life be maintained?
• What is the estimated cost of the recommended treatment plan and ongoing care?
• What can I do at home to best support my dog during this time?

Conclusion:

At Animal Cancer Care Clinic, we are dedicated to providing compassionate and comprehensive care for dogs with hemangiosarcoma. Our experienced team will work closely with you to develop a personalized treatment plan focused on maximizing your dog’s comfort and quality of life. Please do not hesitate to reach out to us with any questions or concerns you may have. We are here to support you and your cherished canine companion through this difficult journey.