Canine Lymphoma: What You Need To Know

Sadly, lymphoma is a fairly common disease in dogs — out of all canine cancer diagnoses, lymphoma makes up 15 to 20 percent. Pet Cancer Awareness Month is the perfect time to learn about this scary yet treatable disease. Here’s what you need to know about canine lymphoma. 

National Canine Lymphoma Awareness Day 

Every Year there is one day also set aside within the Month of November to highlight Canine Lymphoma. National Canine Lymphoma Awareness Day occurs every year on November 7th; the day was first originated by a dog trainer whose dog passed away from canine lymphoma. It’s an important time for pet owners to educate themselves about the signs and symptoms of lymphoma and to make sure their dogs are safe and healthy.  

Basics of Lymphoma 

Lymphoma is a cancer of the lymphocyte, the major white blood cell that’s found in lymph nodes. The lymphatic system includes lymph nodes, spleen, and tonsils, and it works to carry fluid throughout the body and defend the body from infections. Lymphoma can either be centered in a specific area or spread through the whole body; often, cancer starts in the lymph nodes and then spreads to other organs.   

In dogs, there are four primary types of lymphoma:  

• Multicentric lymphoma. Also known as systemic lymphoma, this is the most common kind of canine lymphoma, making up 80-85 percent of canine lymphoma cases. It affects the entire body. 
• Mediastinal lymphoma. This type of lymphoma is rare and affects the chest. 
• Alimentary lymphoma. Fairly common, alimentary lymphoma affects the gastrointestinal tract. 
• Extranodal lymphoma. Extranodal lymphoma is rare and affects organs outside the lymphatic system (such as the kidney, lung, or eyes).

There are 30 types of canine lymphoma altogether. Some are easy to treat because they are slow-moving, while others can be very dangerous if not caught soon enough. Canine lymphoma is very similar to non-Hodgkins lymphoma in humans. 

Symptoms of Lymphoma 

For most dogs who have lymphoma, the first symptom they exhibit is enlarged lymph nodes. You can find lymph nodes under your dog’s jaw and behind the knee; the lymph nodes will feel like hard lumps to the touch. Loss of appetite and general lethargy will also present as symptoms.    Dogs will also exhibit different symptoms based on the specific type of lymphoma they have. Gastrointestinal lymphoma produces symptoms such as diarrhea, vomiting, and weight loss. Mediastinal lymphoma often comes with difficulty breathing as well as increased thirst.  

Lymphoma Tests 

Lymphoma is diagnosed through a simple needle aspiration, a painless procedure where a needle removes cells from a lymph node. Often, dogs will often undergo additional tests that help the veterinarian tell how far cancer has progressed. These tests are generally non-invasive, such as a chest X-ray or a urine analysis. 

Lymphoma Diagnosis 

Most cases of canine lymphoma are treated with chemotherapy; surgery or radiation therapy might be part of the treatment plan, too. Chemotherapy attempts to kill all of the cancer cells so the patient goes into remission. 80 to 90 percent of dogs with lymphoma go into complete remission with an average survival of 12-14 months. 

Some Dogs Are Predisposed 

Middle-aged and older dogs are more likely to be diagnosed with lymphoma. According to the VCA Animal Hospital, there are also several breeds that are predisposed to this type of cancer:  

• Golden Retrievers 
• Boxers 
• Bullmastiffs 
• Basset hounds 
• Saint Bernards 
• Scottish terriers 
• Airedale terriers 
• Bulldogs  

Causes of Lymphoma 

The cause of canine lymphoma is not known. Immune suppression might be a factor; viruses and bacteria could also play a role. Scientists are still working, however, to come up with a definitive answer. 

Nothing in this article should be construed as financial, legal or veterinary advice. Please consult your own advisors for questions relating to your and your pet’s specific circumstances.