Haemangiosarcoma

Description

A highly malignant tumour of vascular endothelial origin. Commonly affect dogs and the most frequently affected areas are the spleen, pericardium, right atrium, liver and muscle. The cat is affected less frequently and the most common sites are the liver, spleen and mesentry. Metastasis occurs via the haematogenous route or via rupture and transabdominal spread. Metastatic sites include, lungs, liver, omentum and diaphram. Surgery is the treatment of choice but even with this survival time remains very short.

Signalment

Often found in German Shepherd Dogs and Golden Retrievers over 9 years of age. Domestic Short haired cats are the most commonly affected cat breed.

• 

  Golden Retriever

  Monika Mężyńska (2005); WikiMedia Commons

• 

  German Shepherd (Alsatian)

  Ellen Levy Finch (22/02/04); WikiMedia Commons

History and Clinical Signs

Can vary depending on the anatomic site that the mass is affecting. Signs such as anorexia, lethargy, weakness, vomiting and anaemia are common. Animals can also present Collapsed following the rupture of the mass, leading to a haemoabdomen or occasionally can be found dead.

In instances where the heart is involved animals may present in heart failure. If there is muscular involvement this often presents as a hard swollen mass.

If the nervous sytem is involved a range of neurological abnormalities will also be present.

Laboratory Tests

Haematology

Anaemia; may be regenerative if due to blood loss, or microangiopathic due to the passage of red blood cells through the microvascular network of the tumour. This also results in the presence of schistocytes in dogs but not cats. A neutrophilia and thrombocytopenia may also be present.

Diagnostic Imaging

Radiography

Useful to look for evidence of metastasis.

Ultrasonography

This is sensitive in indentifying liver and splenic masses where the spleen will show a mixed or nonhomogenoeous pattern and the liver will look hypoechoic or anechoic. It can also be useful to detect metastatic spread.

Biopsy

The only was to to form a definitive diagnosis is following a biopsy and histopathology. This is needed to differentiate haemangiosarcoma from splenic haematoma, haemangioma and accessory splenic tissue.

Pathology

Can be primary in the liver, spleen, right auricle of the heart

distinguished from the superficially similar haemangioma by the presence of much more formed, solid tumour tissue

• accurate prognosis demands histological examination
• secondaries are common locally in the omentum and in the liver

Treatment

Surgery

The treatment of choice for haemangiosarcoma in the dog and cat this is useful if there are any solitary masses that can be excised. All diseased tissue should be removed. Splenic haemangiosarcoma should be treated via splenectomy or a pericardectomy if the pericardium is involved.

Chemotherapy

This will provide a palliative treatment for animals with multiple masses or as an adjuvant therapy post-operatively.

Prognosis

Poor due to high risk of metastasis in the early course of the disease.

References

Ettinger, S.J. and Feldman, E. C. (2000) Textbook of Veterinary Internal Medicine Diseases of the Dog and Cat Volume 2 (Fifth Edition) W.B. Saunders Company.

Hall, E.J, Simpson, J.W. and Williams, D.A. (2005) BSAVA Manual of Canine and Feline Gastroenterology (2nd Edition) BSAVA

Nelson, R.W. and Couto, C.G. (2009) Small Animal Internal Medicine (Fourth Edition) Mosby Elsevier.