Lymphoma is a type of cancer that affects the lymphatic system, which is essential to the immune system. It’s one of the most common cancers in dogs – and to a lesser extent cats – especially as they age. In fact, around 1 in 4 dogs will develop cancer in their lifetime, with lymphoma accounting for nearly a quarter of those cases.
While there is no cure, lymphoma can be effectively managed if caught early. Regular vet visits and knowing the signs to look for can make a huge difference to the quality of your furry friend’s life.
Common types of lymphoma in pets
Lymphoma (also called lymphosarcoma or malignant lymphoma) is a cancer of the white blood cells, similar to Non-Hodgkin lymphoma in humans. It can occur in multiple places around the body at once, including the lymph nodes, liver, gastrointestinal tract and in the bone marrow.
There are several forms of lymphoma seen in dogs and cats, depending on where in the body it develops:
- Multicentric lymphoma: the most common type in dogs, affecting the lymph nodes
- Alimentary (gastrointestinal) lymphoma: affects the stomach or intestines, more common in cats
- Mediastinal lymphoma: affects the chest area and thymus
- Extranodal lymphoma: occurs in organs such as the skin, eyes or kidneys
What causes lymphoma in pets?
There is generally thought to be no one cause of this cancer but some of the risk factors include:
- Genetics: some breeds are more predisposed to this cancer
- Immune dysfunction: chronic inflammation, infections and viruses may play a role in the development of cancer
- Environmental factors: possible exposure to certain chemicals and smoke are associated with an increased risk. This link is still being studied.
What pets are most at risk?
While lymphoma can affect pets of any age, it is more common in senior pets (7+ years).
In dogs, certain purebred and working dog breeds appear to have a higher risk, including Beagles, Bernese Mountain dogs, Boston terriers, Boxers, Bullmastiffs, Chinese Pugs, Doberman Pinschers, English Bulldogs, Flat-Coated Retrievers, French Bulldogs, German Shepherds, Golden Retrievers, Irish Wolfhounds, Labrador Retrievers, Miniature Schnauzer, Pembroke Welsh Corgis, Rhodesian Ridgebacks, Rottweilers, Scottish Deerhounds, Scottish Terriers, Shar-peis, Siberian Huskies, Weimaraners. This increased risk is thought to be linked to inherited differences in the immune system, which may make some breeds more susceptible to cancers affecting white blood cells.
In cats, lymphoma is less strongly linked to specific breeds, although it’s thought Siamese cats may have a slightly increased risk. As with dogs, age remains the most significant factor.
Common signs of lymphoma in pets
Some signs of lymphoma can be mistaken for normal ageing, so it’s important to consult your vet if you notice any of the following:
- Swollen lymph nodes (often felt under the jaw, in front of the shoulders or behind the knees)
- Lethargy or reduced energy
- Weight loss
- Reduced appetite
- Vomiting or diarrhoea (especially with gastrointestinal lymphoma)
- Difficulty breathing (in chest-related cases)
Regular vet check-ups play a key role in early detection.
How is lymphoma diagnosed?
Early detection is now possible for at-risk breeds and senior dogs with a lymphoma screening blood test. This test can be added to a routine senior health screen and can detect lymphoma up to eight months before symptoms appear. Catching the disease early can make a meaningful difference to your pet’s quality of life.
If a screening test is positive, your vet will typically recommend further testing to confirm a diagnosis. This may include a physical exam (such as checking the lymph nodes), additional blood tests, and imaging like X-rays or ultrasound. In many cases, a biopsy is needed for a definitive diagnosis.
Ongoing health monitoring plays an important role in early detection. With a Best for Pet Wellness Plan, annual blood and urine testing is included in your membership, along with unlimited consults, core vaccinations, $250 off dental and more, making it easier to stay on top of your pet’s health.
How to treat lymphoma in pets
The treatment for lymphoma includes chemotherapy which can help control the disease, along with supportive care, including medications to manage the comfort of your pet.
With early detection and the right treatment plan, most pets can achieve remission and continue to enjoy a good quality of life for a little longer. However, sadly most pets will have a recurrence of lymphoma at some stage.
Routine check-ups and screening tests, especially for senior pets, are important for detecting changes as early as possible. If you notice any signs of lymphoma in your pet, book a check-up with your vet.
How to care for pets with lymphoma at home
When caring for a pet with lymphoma, the focus should be on their comfort and quality of life. It can help to provide a balanced, easily digestible diet, keep routines, monitor any changes (behaviour, energy, appetite) and book in regular check-ups.
