Lymphoma (also known as lymphosarcoma) is the cancer of the lymphatic system. This system consists of lymph nodes which act like a drainage system to get infections out of the body. The cells that do this tough work are white blood cells called lymphocytes. They attack foreign invaders in the body and are carried in a clear fluid called lymph. Lymphocytes are carried throughout the entire body. When a dog or a person has lymphoma, this means that they have cancer in the lymophocytes and these cells have invaded the normal tissue.
80% of lymphoma cases are called multicentric, which means that the cancer cells has spread throughout most of the body in many different locations. The spleen, liver, stomach, and intestines are very common areas to find lymphoma in the body.
Symptoms of Lymphoma in Dogs
It’s very hard to pinpoint specific symptoms in dogs when they have lymphoma. Since it can spread all over, it varies case to case. Most often, as with more cancers, weight loss, decreased appetite and lack of energy. Other symptoms are more organ-specific:
- If it’s in the stomach/intestines, vomiting can occur
- Lymphoma in the kidney can cause increased thirst and urination and vomiting
- If it’s in the liver or spleen, weight loss and decreased appetite are very common
- In multicentric lymphoma cases, the lymph nodes are often enlarged
What Causes Lymphoma in Dogs?
Genetics are often to blame and Boxers, Cocker Spaniels, and Labs are the breeds more prone to this type of cancer.
Treatment for Dogs with Lymphoma
Surgery, radiation, and chemotherapy (the conventional treatments) have currently not proven to cure lymphoma in dogs. One good thing to note here, however, is that this cancer is sensitive to chemo and radiation and has a good chance of keeping the disease in remission for longer than other types. Surgery is never performed for lymphoma as it often involves the entire body and there is no way to pinpoint a single mass or tumor.
Doxorubicin is a chemotherapy drug that is often used on dogs with lymphoma. Twice daily radiation has also shown some promise. Bone marrow transplants are a newer approach that allows the dog to receive higher doses of chemotherapy to hopefully keep the lymphoma in remission for a longer period of time.

