Lymphoma in Cats: What Is It and How to Treat It?

Are you worried that your cat might have lymphoma? Perhaps you’ve spotted lumps, changes in appetite, or unexplained weight loss that keep you up at night.

This feeling of uncertainty can be truly unsettling, especially when you only want the best for your beloved feline.

The good news is that with the right knowledge, treatment options, and support, many cats with lymphoma can lead comfortable, fulfilling lives.

Key takeaways

• Lymphoma is a type of feline cancer affecting a type of white blood cell.

• Feline lymphoma shows up in many forms, including mediastinal lymphoma and gastrointestinal lymphoma.

• Early detection and prompt veterinary care can improve prognosis.

• Cats tolerate chemotherapy better than many might think.

• Lymphoma is usually treated through a combination of chemotherapy and supportive measures.

• Positive for feline leukemia virus (FeLV) cats have a higher risk of developing lymphoma.

• Lymphoma cannot be prevented entirely, but certain steps can reduce exposure to viral infections.

Lymphoma is a cancer of the white blood cell known as a lymphocyte. In cats, feline lymphoma is one of the most common cancers, outpacing many other types of feline cancer.

These problematic lymphocytes might appear in various places inside your cat’s body—like the abdomen, chest, or even nasal cavity. The specific location of the lymphoma greatly influences the signs of lymphoma you see.

Why does lymphoma occur?

It begins when the immune cells grow out of control. This can happen for several reasons, including genetic tendencies, viral infections, or even environmental factors.

Feline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) both increase the chance that a cat will develop lymphoma.

Although lymphoma cannot be prevented in every case, isolation of infected cats with FeLV or FIV may help minimise the risk of cross-infection.

Gastrointestinal lymphoma

Gastrointestinal lymphoma—also called intestinal lymphoma or alimentary lymphoma—affects your cat’s gastrointestinal tract (think stomach and intestine).

This form of lymphoma is one of the most common type of lymphoma in cats.

Some felines present with vomiting, diarrhoea, or weight loss because the intestine becomes inflamed or obstructed.

Small cell lymphoma in cats is often a low-grade lymphoma that progresses more slowly, while large cell lymphoma in cats is a high-grade lymphoma that can advance more quickly.

When you hear phrases like small cell gastrointestinal lymphoma or large cell gastrointestinal lymphoma, you’re essentially learning the pace and severity of the cancer.

Mediastinal lymphoma

Located in the chest, feline mediastinal lymphoma (also known as lymphoma in the chest) can cause difficulty breathing.

If fluid builds up around the lungs, your cat might cough or struggle to catch its breath.

Young cats that are positive for feline leukemia virus are more prone to this type.

Multicentric lymphoma

This type of lymphoma in cats involves multiple lymph node regions all at once.

You might notice enlarged lymph nodes around the jaw or other body areas.

Although more common in lymphoma in dogs, cats still experience it.

Nasal lymphoma

Nasal lymphoma affects the nasal passage or sinus area. You may see discharge, sneezing, or difficulty breathing through the nose.

Cats with lymphoma in the nasal region typically have a better prognosis for cats than those with widespread disease, especially if caught early.

Renal lymphoma

Cats with renal lymphoma face kidney involvement, which can lead to changes in thirst, urination, or kidney function.

Because the kidneys are essential for overall health, renal lymphoma can have serious effects if not addressed promptly.

For additional cat-care discussions, see our post on cat-skin conditions to understand other potential health problems that might appear alongside internal issues.

Many clinical signs depend on location and type of lymphoma. However, there are a few universal changes to watch for:

• Weight loss or reduced appetite

• Vomiting or diarrhoea (especially in cats with gastrointestinal disease)

• Swollen lymph node areas

• Breathing difficulty (in cases of lymphoma in the chest)

• Sneezing or nasal discharge (in nasal lymphoma)

• Changes in drinking or urination (in cats with renal lymphoma)

If these clinical signs of lymphoma continue or worsen, it’s crucial to see a veterinary professional.

On occasion, the signs may be subtle, so trust your gut if something feels off.

How vets diagnose lymphoma in cats

Your vet might suggest blood tests, imaging (such as X-rays or ultrasounds), and a biopsy to confirm the presence of lymphoma is suspected. The process to diagnose lymphoma often involves looking at suspicious tissue samples under the microscope.

By identifying malignant lymphocytes—a type of white blood cell—experts confirm that lymphoma is a cancer.

For a more in-depth look at how vets work up illnesses, read how we break down why is my cat snoring to see how thorough an exam can be. Although snoring usually isn’t cancerous, the steps in investigating unusual symptoms are somewhat similar.

Understanding different grades

• Low-grade lymphoma: Also known as small-cell or small cell lymphoma, tends to grow slower. Cats with low-grade lymphoma frequently respond better to gentler chemotherapy.

• High-grade lymphoma: Also called large cell lymphoma, or cats with high-grade lymphoma. This often spreads quickly and may require more aggressive chemotherapy.

Your vet may talk about small cell gastrointestinal lymphoma versus large cell gastrointestinal lymphoma if your cat has gastrointestinal lymphoma. These terms refer to how the cells look under the microscope and how fast they multiply.

Lymphoma is usually treated with chemotherapy. Surgery or radiation therapy may also be considered, depending on where the lymphoma is located.

Each form of feline lymphoma responds differently, so the plan will be tailored to your pet’s needs.

Chemotherapy

Cats tolerate many chemotherapy protocols surprisingly well. While some side effects like reduced appetite or mild lethargy may occur, severe complications are less frequent in cats than in dogs. That said, it’s critical to monitor any adverse reaction closely.

Supportive care

Supportive measures can include appetite stimulants, anti-nausea drugs, and nutritional management. For instance, some kitties show better appetite when offered foods that are easy on the stomach, or warmed slightly.

If you’re searching for more feeding insights, we have an article on what do cats like to eat for breakfast. While it’s not specific to cats undergoing chemo, it might spark ideas.

FeLV and FIV considerations

When your cat is positive for feline leukemia (FeLV) or has FIV, their immune system might be compromised, which can affect response to treatment. Still, many cats diagnosed with lymphoma do well if given proper care and monitored for secondary infections.

Prognosis hinges on factors like location and type of lymphoma, whether it’s low grade lymphoma or high grade lymphoma, and overall health status at diagnosis.

Some cats with low-grade disease can have a longer survival time—often a year or more—especially if they respond well to treatment.

Cats with high-grade lymphoma might need more aggressive therapy. In these situations, lymphoma often moves rapidly, but remission is still possible. With timely intervention, it’s feasible that lymphoma will go into remission.

Lymphoma may recur

Even if lymphoma is diagnosed early and goes into remission, it can come back later. However, many cats do regain a good quality of life for extended periods.

Hearing that lymphoma can occur again can be daunting, but consistent vet checks and monitoring can catch recurrence in its early stages.

Below is a quick comparison to help you spot differences among types of feline lymphoma:

You’re likely wondering how to make life easier for your cherished companion. Below is our single bullet list of helpful tips:

• Regular vet check-ins: Don’t skip follow-ups. Early detection of changes can improve your cat’s response to treatment.

• Comfortable home setup: Provide soft bedding and a quiet rest area. Many cats appreciate a warm blanket or bed in a cosy corner.

• Nutritious meals: If your kitty is fussy, warm the food or opt for strong-smelling treats. Chat with your vet about high-calorie or prescription diets.

• Stress reduction: Keep the environment calm with minimal loud noises and a stable routine. A bit of catnip or a favourite toy can go a long way.

• Monitor symptoms: Jot down any new changes, like breathing difficulty or lumps, and alert your vet promptly.

It’s also vital to keep your cat well-hydrated. If your cat struggles to drink water, talk to your vet about fluid therapy or other solutions. For a broader look at general hydration, you might find our blog on why is my cat drinking a lot of water useful to differentiate normal thirst from potential kidney or metabolic concerns.

While lymphoma cannot be prevented entirely, lowering exposure to FeLV or FIV can reduce the risk of developing lymphoma. Keeping indoor cats away from strays, practicing isolation of infected cats, and ensuring up-to-date vaccinations are crucial steps.

If you’re caring for multiple felines, routine testing for FeLV and FIV helps limit spread. Meanwhile, offering a balanced diet and a stress-free environment keeps your cat’s immune system strong.

"Most cats tolerate it amazingly well and excellent results are possible.  So if finances allow and your vet has said it’s a good option - go for it!" - Aimee, Waggel's expert vet

Lymphoma can live in a cat’s body for varying periods. Some respond so well to chemo that they enjoy many additional months—or even years—of quality life. Others face more aggressive progression. On average, survival time can range from a few months to over a year, especially when lymphoma will go into remission.

High-grade intestinal lymphoma might have a shorter timeline if left untreated, while small cell gastrointestinal lymphoma can provide a longer window. Ultimately, every cat is unique. Regular veterinary appointments and follow-through on medication can help you make well-informed decisions.

No one wants to face cancer in cats alone, and the journey can feel overwhelming at times. If you see anything unusual, or if lymphoma is suspected, please reach out to your vet.

And remember, you don’t have to navigate the emotional side by yourself. Checking in with trusted community members, pet forums, or even a friend who “speaks cat” can lift your spirits.

If you’re exploring insurance options that cover a range of treatments then see our guide to cat insurance here. A quick visit might put your mind at ease and show you how to plan for unexpected costs.

We’re here to walk this path by your side, reminding you that hope and compassion go hand in hand.