What is hemangiosarcoma (HSA)?

Hemangiosarcoma is an aggressive blood vessel cancer that causes tumors on the spleen, liver, and/or heart. HSA can go unnoticed until the tumors rupture, and cause internal bleeding. Some dogs may sporadically bleed internally, with the blood reabsorbed by the body, whereas others experience profuse internal bleeding that suddenly becomes a life-threatening emergency.

What are common HSA signs in dogs?

Early signs include:

• Waxing and waning weakness

• Decreased appetite

• Weight loss

In many, no signs are observed in the early disease stage.

Intermediate to advanced signs include:

• Excessive thirst

• Chills

• Pale gum color

• Abdominal distention

• Panting

• Difficulty breathing

• Inability or reluctance to rise

• Collapse

• Sudden death

How is HSA managed in dogs?  

For splenic or liver HSA, the entire spleen or affected liver lobe is removed, and followed up with chemotherapy. For cardiac HSA, chemotherapy is often recommended as the primary treatment, because surgery can be difficult. Dogs receiving chemotherapy for hemangiosarcoma need regular veterinary visits and diagnostic tests to monitor their status and prognosis. Discussing a personalized management plan with your veterinarian, and a veterinary oncologist, is important for the best outcome for your dog.

What is the prognosis for dogs with hemangiosarcoma?

The prognosis for HSA in dogs is dependent on tumor location and stage, surgical outcome, and medical management response. Because HSA has a high potential for spreading to other organs, the survival time for surgical treatment alone is between 19 and 86 days. Different combinations of chemotherapy with surgery may provide a good quality of life for up to seven months, with a poorer prognosis for cardiac HSA.

Management tips for dogs with hemangiosarcoma   

At-home needs include:

• Easily accessible food and water, and a comfortable location

• Consistency with medications and supplements

• Monitoring appetite, drinking, urination, energy level, and gum color

• Watching for signs of worsening disease

• Avoiding strenuous exercise, if directed by your veterinarian

In a crisis situation:

Contact your veterinarian immediately if your dog becomes lethargic, pants heavily, has difficulty breathing, drinks excessive amounts of water, collapses, or vocalizes in pain.