Printer Friendly


Lymphoma is a common cancer of lymphocytes (white blood cells) in dogs. Between 15 and 20 percent of malignant tumors in dogs are lymphomas. Lymphomas can occur in the lymph nodes, spleen, liver and other organs. The cancer can be aggressive and has a high mortality rate if left untreated.


  • Swelling of lymph nodes
  • Lack of appetite
  • Vomiting
  • Shortness of breath
  • Diarrhea
  • Muffled heart sounds
  • Weight loss
  • Lumps in the skin or mouth

Breeds at Risk 

  • Airedales
  • Bullmastiffs
  • Basset Hounds
  • Golden Retrievers
  • Boxers
  • Saint Bernards
  • Bulldogs
  • Scottish Terriers


Lymphoma in dogs is diagnosed through a combination of tests. Blood tests, fine-needle aspiration of the tumor, biopsies, x-rays and ultrasound are all used to confirm the diagnosis and location(s) of the lymphoma. The exact tests performed will depend on the location of the tumor. A complete blood count, chemistry panel and urinalysis are also recommended. In 15 percent of dogs with lymphoma, the blood calcium level will be higher than normal. Lymphoma generally does not cause pain unless there is bone involvement or severe swelling of lymph nodes.


Lymphoma is a generalized or systemic disease, which makes surgery and radiation impractical in most cases, so treatment consists of chemotherapy. A wide variety of anticancer agents and chemotherapy protocols are currently used to treat lymphoma. The treatment usually consists of a combination of oral and injectable drugs given on a weekly or monthly basis. Some commonly used drugs include cyclophosphamide, vincristine, doxorubicin and prednisone. The exact treatment protocol will vary depending on your veterinarian’s approach. Almost all dogs tolerate chemotherapy very well, and the quality of life should be very good during treatment period.


The life expectancy of untreated dogs with generalized lymphoma is about 4 to 6 weeks after diagnosis. In dogs that undergo one of the recommended protocols, life expectancy can be extended to a year on average and occasionally longer.

Treatment for lymphoma can often be performed by a local veterinarian, so there is no need to travel long distances to a veterinary school or specialty clinic. However, a cancer specialist has a great deal more experience, specialized skills and access to some newer treatment options. One year can be almost 10 percent of a dog's expected life span, so the remission rate and increased life expectancy with lymphoma treatment is often well worth it to pet owners, especially when the quality of life remains good.

Current Research

Click here to find out about Morris Animal Foundation--funded research into lymphoma.

Morris Animal Foundation urges pet owners not to implement any suggestions on animal health treatments without prior consultation with their licensed veterinarian. If your pet is experiencing health issues, contact your licensed veterinarian. The Foundation funds research to enhance medical options available to veterinary professionals and their patients.