Heart Tumors in Cats and Dogs
What are heart tumors?
The heart is a muscular organ responsible for pumping blood through the blood vessels by repeated, rhythmic
contractions. Abnormal growth can occur in different parts of the heart, including the pericardium, heart base, or the
myocardium. Heart tumors are not common in dogs and are even more rare in cats. When they do occur, they typically
affect middle-aged to older dogs (7-15 years) and there is some evidence that German shepherds and Golden retrievers
may be at increased risk for developing this type of cancer. Primary heart tumors may be either benign or malignant

Source: www.vin.com/ImageDBPub/VP05000/IMG02220.GIF

How common are heart tumors in cats and dogs?
Heart neoplasms (abnormal growth of cells) are not common in dogs and are even more rare in cats. Based on available
data, the overall incidence of heart tumors  is estimated to be 0.19% in dogs and 0.0275% in cats. The most common heart
tumor in cats is lymphosarcoma, and the most common heart tumors in dogs are
heart hemangiosarcoma (malignant
tumors arising out of the blood vessels), followed by
aortic body tumors (also known as chemodectoma). The following
chart illustrates the classification of the different heart tumors that exist in cats and dogs.

Source: www.vet.uga.edu/vpp/clerk/bement/index.php

To learn more about diagnosis, symptoms, treatment options and prognosis of specific heart tumors,
please click on the below heart tumor subtype links:
Heart hemangiosarcomas        
Aortic body tumors     

Does cancer cause pain in cats and dogs?
Pain is common in pets with cancer, with some tumors causing more pain than others. In addition to pain caused by the
actual tumors, pets will also experience pain associated with cancer treatments such as surgery, radiation therapy or
chemotherapy. Untreated pain decreases the pet's quality of life, and prolongs recovery from the illness, treatment or
injury. It is, therefore, essential that veterinary teams that are taking care of pets with cancer should also play a vital role in
educating pet owners about recognizing and managing pain in their pets. The best way to manage cancer pain in pets is to
prevent it, a term referred to as preemptive pain management. This strategy anticipates pain ahead of time and
administers pain medication before the pet actually experiences pain, thus ensuring the pet's maximum comfort.  To learn
more about which tumors are likely to cause a lot of pain, how to recognize pain in pets with cancer and what cancer pain
management options are available for your pet, please visit the
Cancer Pain Management section.

How important is nutritional support for pets with cancer?
Cancer cachexia (a term referring to progressive severe weight loss) is frequently observed in pets with cancer. Pets with
cancer lose weight partly because of lack of appetite and partly because of cancer-induced altered metabolism. Some of
the causes for decreased appetite are related to the cancer itself (for example, tumors may physically interfere with food
chewing, swallowing, and digestion process) and some may be related to the side effects of cancer treatment (for example,
some chemotherapy drugs cause nausea and vomiting, and radiation therapy can cause mouth inflammation).

Proper nutrition while undergoing cancer treatment is essential to maintain your pet's strength, improve survival times,
quality of life and maximize response to therapy. Adequate nutritional support was shown to decrease the duration of
hospitalization, reduce post-surgery complications and enhance the healing process. Additionally, pets with cancer need to
be fed diets specifically designed to provide maximum benefit and nutritional support for the patient. To learn more, please
visit the
Cancer Nutrition section.

How do I find a qualified veterinary oncologist?
To locate a qualified veterinary oncologist worldwide who can discuss with you appropriate cancer treatment plan for your
pet's cancer condition, please visit the "
Locate a veterinary oncologist" section.  

Additional resources

  • Withrow Stephen J, and David M. Vail. Small Animal Clinical Oncology. St Louis: Saunders Elsevier, 2007.
  • Morrison Wallace B. Cancer in Dogs and Cats: Medical and Surgical Management. Baltimore: Williams&Wilkins, 1998.
Comprehensive guide to cancer diagnosis and treatment in cats and dogs
© 2007 Pet Cancer Center. ALL RIGHTS RESERVED.
Last updated 2/19/2017