Lymphoma in Cats: Understanding Feline Lymphatic Cancer
Lymphoma is the most frequently diagnosed cancer in cats, making up about 30% of all feline cancers. This disease targets lymphocytes—white blood cells that play a crucial role in the immune system. Because lymphocytes travel throughout the body, lymphoma doesn't stay put; it can pop up in many different places, making it a systemic condition.
Where Does Lymphoma Strike?
Cats can develop lymphoma almost anywhere lymphocytes live or travel. The most common sites include:
- Gastrointestinal tract (alimentary/intestinal)
- Lymph nodes
- Chest cavity (mediastinum)
- Kidneys
- Liver
- Spleen
- Bone marrow
- Nasal cavity
The specific symptoms and outlook depend on where the cancer shows up and how aggressive it is.
Main Types of Lymphoma in Cats
- Alimentary (intestinal) lymphoma: The most common form, especially in older cats. Signs often include weight loss, vomiting, diarrhea, appetite changes, and sometimes a lump you can feel in the belly.
- Mediastinal lymphoma: Found in the chest cavity near the thymus and regional lymph nodes. Younger cats with feline leukemia virus (FeLV) are at higher risk. Breathing problems often occur due to fluid buildup or masses pressing on the lungs.
- Renal lymphoma: Affects the kidneys, leading to increased thirst and urination, vomiting, weight loss, and poor appetite. This type often spreads to the nervous system and usually has a worse prognosis.
- Multicentric lymphoma: Involves several lymph nodes or organs at once. It's less common but possible—especially if the cat has retroviral infections.
- Nasal lymphoma: Tumors grow inside the nasal cavity, causing sneezing, nasal discharge, and sometimes swelling of the face.
What Puts Cats at Risk?
A few key risk factors make some cats more likely to develop lymphoma:
- Infection with FeLV (feline leukemia virus) or FIV (feline immunodeficiency virus)
- Exposure to tobacco smoke
- Certain genetic backgrounds
- Poorly understood environmental influences
The FeLV vaccine has helped reduce some forms of lymphoma but can't prevent them all.
Symptoms: What Should You Watch For?
The signs vary depending on where the cancer is located but may include:
- Weight loss
- Lethargy or decreased activity
- Vomiting or diarrhea
- Poor or altered appetite (sometimes increased appetite)
- A mass or swelling in the abdomen
- Trouble breathing if there's chest involvement
- Drinking and urinating more than usual (especially with kidney involvement)
- Nervous system symptoms if spread occurs there
- Swellings under the jaw, near shoulders, or behind knees (enlarged lymph nodes)
- Sneezing or nasal discharge for nasal lymphoma cases
Diagnosing Lymphoma: How Vets Find It
Your veterinarian may use several tools to diagnose lymphoma:
- A thorough physical exam to check for lumps or enlarged nodes
- Blood tests and urinalysis to assess health and rule out other problems
- X-rays or ultrasound scans to spot tumors inside organs or cavities
- Tissue samples (biopsies) or fine needle aspirates for microscopic analysis
- Advanced tests like flow cytometry or immunohistochemistry for detailed cell typing
- Testing for FeLV/FIV status since these impact treatment choices and prognosis
A definitive diagnosis usually means getting a tissue biopsy—either surgically or with an endoscope. Pathologists then determine whether it's high-grade (fast-growing) or low-grade (slow-growing), which helps guide treatment decisions.
Treatment Options: What Can Be Done?
Treating feline lymphoma almost always involves chemotherapy because it's rarely confined to one spot. Here’s how therapy typically breaks down:
- If it's high-grade lymphoma:Aggressive multi-drug chemotherapy protocols are used—often including cyclophosphamide, doxorubicin, vincristine, L-asparaginase, and prednisolone. Remission happens in about 50-75% of cases; median survival is 6-9 months. Side effects are usually mild; only around 10% of cats get significant nausea or bone marrow suppression. </div>
- If it's low-grade intestinal lymphoma:This slower form responds well to oral medications like prednisolone and chlorambucil. Most cats do well; average survival time is 1.5–2 years—and some live even longer. Symptoms can return after months or years because remission isn't a cure.</div>
- If owners can't pursue full chemotherapy:Palliative care with prednisolone alone can provide temporary relief for 2–4 months.</div>
- Surgery & radiation therapy:Might help with isolated tumors (like nasal forms), but aren't curative alone.
The Outlook: Prognosis for Cats With Lymphoma
The outcome depends on many things: where the disease started, how advanced it is at diagnosis, FeLV/FIV status, overall health of your cat, response to initial treatment—and sometimes just luck. Generally speaking:
- Cats with untreated lymphoma survive about four weeks after diagnosis.
- Palliative prednisolone gives two to three months on average.
- Chemotherapy brings remission for 50–75% of cats; survival ranges from six months (for aggressive types) up to two–four years for low-grade intestinal forms.
- Cats tend to tolerate chemotherapy well; side effects are mild compared to people—hair loss is rare!
- The focus stays on quality of life during treatment; most cats don't seem sick while receiving therapy.
- Cats with renal/multicentric forms have worse outcomes than those with localized/low-grade disease.
Can You Prevent Lymphoma?
You can't always prevent this cancer—but you can lower your cat's risk by taking these steps:
- Vaccinate against FeLV and avoid exposure to infected cats.
- Avoid tobacco smoke in your cat's environment—it increases risk significantly!
- Bump up regular vet checkups as your cat ages so any warning signs are caught early.
Catching lymphoma early—and tailoring therapy appropriately—can make a big difference for both lifespan and quality of life in affected cats. If you notice anything unusual about your cat's appetite, weight, energy level—or see new lumps—don't wait: reach out to your veterinarian promptly!
