Lymphoma in Dogs

Lymphoma or Lymphosarcoma is a common cancer in older dogs. It is an aggressive an malignant cancer that spreads quickly and has a high mortality rate if left untreated. Lymphoma usually strikes dogs between the ages of five and nine years, but any dog may come down with lymphoma.

What is Lymphoma

Lymphoma is the malignant cancer of the lymph nodes. The lymph nodes and lymphatic system run throughout the dog’s body because it is the body’s defense system against infections such as bacteria and viruses. When the lymph nodes have cancer, it can spread throughout the body rapidly.

Types of Lymphoma

There are various types of lymphoma. The multicentric form appears in the lymph nodes. Another form, called lymphoblastic leukemia appears in the bone marrow. Lymphoma can take the gastrointestinal form where it appears in the stomach and GI tract. Lymphoma can also start in the skin, called the cutaneous form. A form of lymphoma is called thymic lymphoma which takes the mediastinal form in an organ called the thymus near the heart.

There are other forms of lymphoma which can appear in the kidneys, nervous system or nasal cavity, but these are less common.

Symptoms

Symptoms of lymphoma include swollen lymph nodes (under the jaws, behind the knees or in front of the shoulders. If the GI system is affected, the dog may vomit and have diarrhea, may lose weight and may not want to eat. The cutaneous form may show tumors on the skin and have itchy, flaky skin. Other symptoms include difficulty breathing, lethargy, and increased thirst and urination.

Time Frame

Without treatment, dogs diagnosed with lymphoma are most likely to live only four to six weeks. Depending on the treatment, a dog can live between eight months to almost two years, giving the dog and owner extra time. In many cases, the lymphoma will go into remission with more than 75 percent of dogs living for a year.

Treatments

Lymphoma is commonly treated with chemotherapy, radiation, and other medications, depending on the type of lymphoma and the protocol used. Some less aggressive protocols may only give a few weeks, while other protocols can give the dog six months to a year or more. Talk with your veterinarian over what protocols make sense for your dog.

Most dogs do well with chemotherapy and do not experience the same problems (baldness, sickness) that humans have in the past. Dogs who undergo treatments usually live a good quality of life while on chemotherapy and while the cancer is in remission. When the cancer returns, there is only a 40 percent chance of a second remission and even less for a third remission.

Should You Treat Your Dog for Lymphoma?

It’s no doubt that you’re going to have to weigh cost with the amount of time you get with your pet. Some protocols are fairly cheap (giving prednisone only, for example) but will only yield about 60 days. With most treatments, chemotherapy and radiation can give a good quality of life. When you consider that you can give your dog a year to two years, which in many dogs is 10 to 20 percent of their life, the cost of treatment may seem worth it. This is something you need to talk with your veterinarian about to understand all your choices and options available to you and your dog.

References

Cancer and Your Pet: The Complete Guide to the Latest Research, Treatments, and Options by Debra Eldredge and Margaret H. Bonham, 2005.

Peteducation.com: Lymphoma in Dogs

CanineCancer.com: Lymphoma

Petplace.com: Lymphosarcoma (Lymphoma) in Dogs

VeterinaryPartner.com:Lymphoma in Dogs