Symptoms of Lymphoma in Dogs

Canine lymphoma, or lymphosarcoma, is cancer of the lymph nodes that accounts for about 20 per cent of malignancies in dogs. This disease is not gender specific, but some breeds including boxers, golden retrievers, and West Highland white terriers (Westies) are susceptible.

There are several types of canine lymphoma; precise diagnosis requires testing by a veterinarian. Initial diagnosis can be difficult because many of the symptoms of canine lymphoma occur in other serious canine diseases. Any one of several symptoms should prompt a visit to the veterinarian.


Hard, round lumps on your dog's abdomen, armpits, back or neck are a warning sign requiring evaluation by your veterinarian. These lumps are not the same as the soft and flexible fatty deposits common in older dogs Your veterinarian may take a cell biopsy from a lump to determine the presence of lymphoma or other cancers.

Digestive Problems and Weight Loss

Refusal of food or greatly reduced food intake can indicate serious disease including lymphoma. A hearty eater that stops eating should be seen by your veterinarian. Prolonged loss of appetite leads to weight loss, and sudden weight loss suggests serious illness. Swollen lymph nodes can interfere with food consumption. Pain and difficulty swallowing may discourage your dog from eating. Some forms of lymphoma interfere with the gastrointestinal tract, spleen and liver, which can cause digestive distress, vomiting and diarrhoea.

Respiratory Distress

Enlarged lymph nodes can interfere with breathing. Dogs with lymphoma may cough or "hack" repeatedly due to airway obstruction caused by swollen lymph nodes.Symptoms can worsen as tumours grow.

Inactivity and Depression

A formerly active and energetic dog that loses interest in its surroundings, fellow pets and human family should be seen by a veterinarian. Lymphoma can interfere with a dog's ability to breathe and to swallow food, which can cause weakness and lethargy. Lymphoma affecting a dog's bone marrow can cause weakness due to inability to produce sufficient blood cells.


Diagnosing canine lymphoma requires a physical exam and tests. A blood test is available that can diagnose lymphoma from a small blood sample. This test is minimally invasive and highly accurate. Your vet may also order blood tests including complete blood count (CBC), a blood chemistry panel and urinalysis. In cases where lumps are present, a biopsy or aspiration of cells may be done. Many dogs are in advanced stages of lymphoma by the time they display symptoms, but your veterinarian may refer your dog to a veterinary oncologist for chemotherapy depending on your dog's condition and age. Lymphoma is not curable, but chemotherapy can lead to remission lasting a few months. Dogs diagnosed with lymphoma and displaying symptoms typically do not survive beyond a few weeks without treatment.