Lymphoma in Dogs

What is lymphoma?

Lymphoma is a cancer of white blood cells, which circulate through the blood and especially through a special circulatory system called the lymphatic system (made up of a network of lymphatic vessels and lymph nodes). This system is as extensive throughout the body as the venous and arterial bloodstreams. Normally the function of the lymphatic system is to filter out debris from dead cells and bacteria and produce antibodies against foreign substances encountered throughout the animal’s life. In dogs, lymphoma is a rapidly progressive disease that, if left untreated, results in death within a relatively short time, usually a few weeks from the time of diagnosis.

What causes lymphoma?

What causes a healthy cell to be transformed into a tumor cell is still largely unknown. Much research has been conducted in recent years concerning lymphoma.

What are the clinical signs?

Lymphoma is recognized in several clinical forms:

  • Generalized
  • Intrathoracic (in the chest)
  • Skin
  • Gastrointestinal
  • Leukemia (circulating in the bloodstream)

The most common sign is painless enlargement of the lymph nodes. Because the disease affects the whole body, any organ system can be affected and non-specific signs may occur, including:

  • Depression
  • Weakness
  • Weight loss
  • Loss of appetite
  • Diarrhea
  • Vomiting
  • Difficulty breathing

Often dogs with lymphoma are slightly anemic. The liver and spleen can also be involved and enlarged in size.

Can lymphoma be cured?

We are unable to cure canine lymphoma. However, the vast majority of dogs can be placed into complete remission for many months. Their quality of life during this period is generally excellent.

What does treatment consist of?

Because lymphoma can affect every organ system, the entire body must be treated. This leaves chemotherapy as our most effective means of killing the rapidly growing and dividing cancer cells. Some drugs are given intravenously and some orally. Many times a comination of drugs are administered.

Isn’t chemotherapy more harmful than the disease?

No. Any chemotherapy drugs we recommend provide benefits by their actions against the cancer cells that are expected to far outweigh any potential side effects associated with their use. We will try to outline the side effects you might see following chemotherapy and give you recommendations as to what can be done to monitor and prevent them.

What is life expectancy with treatment?

Generally, the second remission is shorter than the first. Sometimes a third, fourth and even fifth remission can be achieved, but each is generally shorter than the last as the cancer cells become resistant to the chemotherapy. On average, with treatment, patients will live for approximately 1 year. However, every dog is an individual and some will live much longer than this.

Sometimes, additional diagnostic tests that tell us more about the location or type of lymphoma will also give us more information to help predict prognosis. Ultimately, the only way to know how well any specific patient will respond is to start treatment.

How will I know when it is time to say good-bye?

 We will help you with that difficult decision in any way we can.  We will also do everything we can to make sure that it is not for many months to come.  Nobody knows your pet better than you do and they will let you know when their quality of life is no longer acceptable.  It is rarely anything specific.  Trust yourself.  Don’t hesitate to ask all of your questions.  We will work together as a team and the most important members are you and your pet.

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