Hemangiosarcoma of the Spleen in Dogs

Hemangiosarcoma of the spleen, also called angiosarcoma, is an aggressive cancer of the soft tissue in the spleen. This soft tissue is vascular, arising from cells that constitute the lining of small blood vessels. Hemangiosarcoma is metastatic, meaning the cells can transfer from one organ or tissue to another.  The malignant tumors that form in the spleen can rapidly grow to over ten pounds. This condition is commonly seen in German shepherds but can affect other breeds.

Symptoms of Hemangiosarcoma of the Spleen

Hemangiosarcoma of the spleen can arise spontaneously with a rapid onset of symptoms. Some dogs do not show any signs of illness prior to advanced stages of the disease. Dogs that are symptomatic may show signs such as:

  • Lethargy
  • Loss of appetite
  • Weight loss
  • Difficulty breathing
  • Abdominal swelling (occasionally subsiding and recurring)
  • Visible bleeding (usually nosebleeds)
  • Pale gums and eyes
  • Rapid breathing

Hemangiosarcomas of the spleen can be fatal if the mass breaks open and bleeds heavily. If this occurs the dog may appear weak, very cold and have pale gums. The bleeding may stop suddenly, with the dog showing recovery that is only temporary. The masses will open and bleed repeatedly, eventually causing death.

Diagnosis of Hemangiosarcoma of the Spleen in Dogs

A routine physical examination by a veterinarian may show a large firm mass in the abdominal region. Abdominal radiographs (x-rays) may be done to determine that the mass is on the spleen. Additional radiographs of the chest should be done to determine if the cancer has spread to the heart. Growths may not be felt or may not be clearly visible on radiographs if the dog is overweight or very large.

Basic laboratory blood work can also help accurately diagnose hemangiosarcoma of the spleen. The blood work may show anemia that is indicative of the spleen bleeding. Aspiration of fluid from the abdomen can also be done to determine if the fluid is blood tinged due to bleeding of the spleen.

DIC, or disseminated intravascular coagulation, is a common blood clotting disorder that may accompany hemangiosarcoma of the spleen. Dogs suffering from DIC may show decreased platelet counts in blood work. The disorder will also cause blood to take longer to clot when it is drawn into a syringe. DIC is a common cause of death in many dogs suffering from hemangiosarcoma.

Treatment of Hemangiosarcoma of the Spleen

If the spleen has a mass that is bleeding profusely and that cannot be stopped with pressure wraps, the dog may require an emergency splenectomy. The splenectomy procedure involves removal of the spleen and, if possible, the primary tumor. If the dog has lost an excessive amount of blood, blood transfusions may be necessary prior to surgery. In these cases an iron supplement will be recommended to aid in recovery from surgery. Successful removal of the spleen and primary tumor will still require chemotherapy after surgery, if a veterinarian determines that the treatment could be effective.

The chemotherapy doxorubicin will be administered intravenously every 3 weeks, for approximately 12 to 18 weeks of treatment total. Treatment with chemotherapy may increase survival time by up to 6 months. Regular physical examinations that include radiographs and laboratory blood work will be necessary after chemotherapy treatments are complete.