Lymphoma in cats is a cancer of their body's immune defence cells. It’s one of the most common types of cancer, affecting up to 1 in 2000 cats every year. Lymphoma in cats is rarely curable. Treatment aims to control the cancer and to improve the symptoms. Lymphoma can develop in any cat, but it’s most likely in older cats, males and unvaccinated cats.

Lymphoma in cats happens when lymphocytes start to multiply out of control. Lymphocytes are a type of white blood cell, part of the body's immune defence system. There are different types of lymphoma in cats, which affect different parts of the body. Symptoms will depend on the location and spread of the cancer. Life expectancy with treatment is on average 6-12 months. Life expectancy depends on the type of lymphoma, stage and response to treatment. Outlook for remission is best when the lymphoma is identified and treated promptly. Call a vet as soon as possible if you’re worried your cat may have symptoms of lymphoma.

What is lymphoma in cats?

Lymphoma accounts for 33% of cancers in cats diagnosed by vets each year.

• Lymphoma is a cancer of white blood cells called lymphocytes.

• Lymphocytes are made in the bone marrow. They help the body to fight infection and disease.

• Lymphoma usually develops in lymphoid tissue, the body’s ‘battlegrounds’ against infection.

• There are different types of lymphoma in cats, including gastrointestinal (abdominal), mediastinal (chest), renal (kidney), multicentric (lymph glands), nasal (nose) and cutaneous (skin)

• Lymphocytes travel throughout the body, so the cancer spreads easily to multiple organs or tissues

• Lymphoma in cats can rarely be cured. It will eventually result in death.

• Life expectancy with treatment is 6-12 months, occasionally longer, but less without treatment or with poor response to treatment.

Types of lymphoma

• The most common type of lymphoma in cats, around two-thirds of lymphoma cases

• Affects the stomach, intestines, and lymph nodes inside the tummy

• Occurs in the chest cavity, between the lungs

• Associated with Felv and FIV infection

• Much less common with increased vaccination

• Unusual type of cancer as mainly affects younger cats

• Much less common in cats than in dogs

• Affects multiple tissues and organs

• Usually discovered when external lymph glands under the skin become enlarged

• Affects the kidneys

• May spread to the brain and spinal cord

• Most common nasal tumour of cats

• Second most common cause of nasal disease in cats

• Uncommon in cats

• Skin lumps can be found anywhere and may become ulcerated

What are the symptoms of lymphoma in cats?

Symptoms of Lymphoma in cats will depend on type of lymphoma and organs or tissues involved Intestinal lymphoma:

• Vomiting and diarrhoea

• Unexplained weight loss

• Changes in appetite: usually eating less, occasionally more.

• Changing tummy shape: Developing a swollen tummy or a firm mass you can feel through the skin

Mediastinal Lymphoma:

• May develop suddenly

• Coughing

• Breathing rapidly

• Having difficulty breathing

• Not eating

Multicentric Lymphoma:

• Painless swelling of one or more of your cat’s peripheral lymph glands

• 5 pairs of lymph glands just under the skin can be easily felt if enlarged

  • Submandibular (beneath the angle of the jaw area;

  • Prescapular (in front of the shoulder blade, near the chest);

  • Axillary (armpit);

  • Inguinal (inside the thigh, in the groin);

  • Popliteal (behind the knees).

Renal Lymphoma:

• Drinking more

• Urinating (peeing) more

• Eating less

• Vomiting

Nasal Lymphoma:

• Sneezing

• Noisy snuffly breathing

• Runny nose

• Runny eyes

• Nose bleeds

• Developing an abnormal face shape or facial pain.

Cutaneous lymphoma:

• Variable skin changes: nodules, masses, ulcers, bald flaky patches

High blood calcium level (hypercalcaemia) is a serious complication with some types of lymphoma Associated symptoms include:

• Drinking more

• Urinating (peeing) more

• Irregular heartbeat: weakness, loss of energy, collapse.

Which cats are most at risk of getting lymphoma

Any cat can get lymphoma, but there are certain recognised risk factors:

• Being middle-aged to older, except for mediastinal lymphoma

• Being male

• Being unvaccinated

• Being exposed to environmental pollutants and toxins, for example, cigarette smoke increases your cat’s risk of nasal lymphoma

Lymphoma cases are more likely to be diagnosed in insured cats than uninsured cats. This suggests that investigation of the symptoms is more likely in insured cats. And indicates the welfare benefits of insurance.

Risks to people and other cats

• Lymphoma is a disease of individual cats. It won't spread between cats or from cats to other people or animals. The exception is lymphoma associated with Felv or FIV infections.

• Cats who share the same age, sex and environmental factors will be equally at risk.

• Chemotherapy drugs to treat Lymphoma are hazardous to cats and people they’re not prescribed for. Careful handling and strict hygiene are essential.

How do vets diagnose lymphoma in cats?

The first stage of diagnosis of lymphoma in cats is usually the symptoms and a physical examination. Vets carry out further tests to confirm the diagnosis.

• Fine needle aspirate: Collecting cells from a lump or swelling to examine under a microscope

• Biopsy: Removing a larger piece of the lump or a whole lymph gland for more detailed assessment.

Once the diagnosis is confirmed, further tests check the spread and effects elsewhere in the body:

• Chest x-rays and abdominal ultrasound

• Blood tests

Your vet may advise referral to a cancer specialist, an oncologist, for further investigation and treatment.

Finding out more about the type of lymphoma, the stage (spread) and the best treatment options:

• Advanced imaging: MRI, CT scan

• Urinalysis

• Bone marrow aspirates: collecting samples where lymphocytes are made

• IHC (immunohistochemistry): This can help to identify the type of lymphoma.

How can vets treat lymphoma in cats?

There’s no cure for lymphoma in cats. The treatment goal is remission. This means reducing the symptoms and signs of the cancer. And above all, maintaining your cat’s quality of life.

The best treatment available for lymphoma is chemotherapy. Chemotherapy drugs kill cancer cells. There are multiple drugs and combinations of drugs used to treat lymphoma in cats. 3 drugs are commonly used:

• Cyclophosphamide

• Vincristin (Oncosin)

• Prednisolone

Each of these drugs acts against cancer cells in a different way. But they are even more effective when used in combination to tackle the cancer cells from multiple angles. This is called the COP protocol.

• Treatment begins with a higher ‘induction’ dose to maximise the effect

• Medication dose and frequency reduces over the next 4 weeks to reach a maintenance level

• Chemotherapy may stop after 6-12 months. This will depend on the protocol your vet uses and your cat’s response to treatment

Side effects are relatively mild on this protocol, but can include

• Vomiting and diarrhoea

• Reduced appetite

A 4th drug may be added in:

• Doxorubicin (Hydroxydaunorubicin)

This is the CHOP protocol. CHOP and the more complex individual protocols may achieve remission where simpler treatments fail. However, this comes at the cost of greater risk and severity of side effects.

Radiotherapy is occasionally used alongside chemotherapy for some types of lymphoma, especially in the skin

Chemotherapy will not be a practical option in every case.

Things to consider include:

• Giving your cat multiple medicines

• Attending regular clinic appointments

• Cost

• Likelihood of remission

• Quality of life

Palliative care options can include

• Prednisolone: steroid medication

• Pain relief

• Appetite stimulants

• Special supportive prescription diets

How far you take the investigation and treatment of lymphoma in your cat is an individual decision. There’s not a one-size-fits all approach. Talk things through with your vet and all those who share your cat’s care to make the best decision.

How to care for a cat with lymphoma at home

There are no home remedies for lymphoma in cats. During their illness and any treatment, the best we can do is to prioritise their quality of life.

• Give all medicines exactly as prescribed by your vet

• Handle chemotherapy drugs carefully and dispose of packaging or unused medicine as directed by your vet

• Always wear gloves if cleaning up after a cat on chemotherapy

• Let your cat rest in a warm, quiet and comfortable place

• Feed a high-quality diet. This may be a special prescription diet, such as Hills Prescription Diet On-Care or a/d, where appetite is poor.

• Keep a careful eye on your cat’s breathing rate and depth, urine and faeces (poo) production and weight changes.

• Keep your cat indoors. Some may benefit from supervised time in the garden

Even with intensive treatment, life expectancy for cats with lymphoma is unlikely to be more than a year. At some point their health will deteriorate and their quality of life will worsen. When this happens, euthanasia is the kindest option. By this time you will have travelled a traumatic and heart wrenching journey with your cat. Talk to your vet and those who share your cats care early on about how and when you will make this decision together. Monitoring quality of life regularly and objectively with the accompanying tool may help.

Assess quality of life

Can lymphoma in cats be prevented?

There is no guaranteed way to prevent lymphoma in cats. There’s rarely one absolute cause and multiple things can contribute to risk. Early identification of cancer offers the best chance of achieving remission.

• Check your cat regularly for new lumps - when stroking them or playing together

• Attend regular vet health checks

• Keep up-to-date with vaccinations and preventive treatments

• Feed a high-quality and balanced diet

• Keep your cat slim, with a healthy body condition score

When to worry about your cat with lymphoma

Contact your nearest vet if your cat with lymphoma is:

• Unconscious or unable to respond to you

• Having difficulty breathing: open mouth, gasping, distressed

• Vomiting with fresh blood or passing black tarry stools

• Having a seizure for the first time

Call a vet if your cat has:

• A new lump

• Lost a lot of weight for no apparent reason.

• Developed sneezing and nasal discharge

Joii can help with:

• Treating simple causes of vomiting and diarrhoea

• Giving medicine to cats

• Assessing quality of life

• Diets for health and recovery.