Lymphoma (Lymphosarcoma) in Dogs and Cats

Causes of lymphoma in dogs and cats
Even though lymphoma cancer is quite common in dogs and cats, there are no proven specific causes found in most cases. Although genetic predisposition is suspected, many holistic veterinarians believe that environmental factors, including overvaccination, toxic pet foods, and chronic reactions to chemical pesticides may play a role in some pets with lymphoma. Prolonged use of immune-suppressive medications may also lead to immune system breakdown and cancer development.

Pets most at risk for lymphoma
In cats, lymphoma can occur in both young and older pets. Cats under one year of age that test positive for feline leukemia or feline immunodeficiency virus may develop cancer of the thymus and lymph nodes in the chest cavity. This type of lymphoma is known as mediastinal lymphoma. Older cats may typically develop cancer in a wider variety of areas including the peripheral (external) lymph nodes, digestive tract, kidneys, eyes, skin, nasal cavity, and central nervous system. There does not seem to be any specific breed predilections in cats. In dogs, certain breeds may be more prone to lymphoma, including Airedales, Bulldogs, Golden Retrievers, Boxers, Basset Hounds, Schnauzers, Saint Bernards, and Scottish Terriers. Middle aged to older dogs are more likely to be affected.