FR
ENWhat is feline lymphoma?
Lymphoma (or lymphosarcoma) arises from the abnormal proliferation of lymphocytes, white blood cells playing a key role in immune response. It is the most commonly diagnosed cancer in cats; it can occur at any age, but cats over 9 years old are most frequently affected.
The lymphatic system
Understanding this system helps explain why lymphoma can affect so many different regions of the body and produce such varied symptoms.
Thymus
Maturation of T lymphocytes; very active in young cats.
Spleen
Blood filtration, white blood cell storage, immune response.
Bone marrow
Production of all blood cells, including lymphocytes.
Lymph nodes
Cervical, axillary, inguinal, popliteal: filters of the immune system.
Lymphatic vessels
Network transporting lymph throughout the entire body.
Lymph transports and ensures
The main types of feline lymphoma
The type and location of lymphoma determine symptoms, treatment options, and prognosis. The gastrointestinal type is by far the most common in cats.
Gastrointestinal (alimentary)
Affects the stomach, small intestine, or colon. Often presents as chronic enteropathy: vomiting, diarrhea, progressive weight loss. Sometimes confused with IBD (inflammatory bowel disease).
Mediastinal (thoracic)
Located in the chest (mediastinal region). Often associated with FeLV. Can cause fluid accumulation in the thoracic cavity, compressing the lungs.
Multicentric
Affects superficial and deep lymph nodes. Often associated with FeLV and FIV. Thanks to FeLV vaccination, this form has significantly declined.
Cutaneous
Chronic wounds, lesions, scaling, or ulcers that don't heal despite standard treatments. May affect the face, ears, or trunk.
Other locations
Nasal lymphoma (sneezing, discharge), renal, central nervous system, or oral cavity. Each location requires a specific workup and protocol.
Mediastinal and multicentric forms are frequently associated with FeLV and FIV. Thanks to vaccination and declining FIV incidence, these presentations have decreased; unvaccinated outdoor cats remain at risk.
Studies suggest an association between exposure to tobacco smoke and a higher incidence of gastrointestinal lymphoma in cats. Avoiding smoking near your cat is a simple and effective preventive measure.
Signs and symptoms
Initial signs are often mild and non-specific; it is frequently progressive weight loss or persistent digestive issues that alert owners. Symptoms vary depending on the location of the lymphoma.
Early stage
- •Clingy behavior or, conversely, withdrawal
- •Mild or intermittent cough
- •Unkempt coat, reduced self-grooming
- •Mild vomiting or diarrhea
- •Reduced appetite
Intermediate stage
- •Unable or reluctant to play
- •Difficulty finding a comfortable position
- •Mild to severe weight loss
- •Nausea, more pronounced appetite loss
- •Possible increased thirst (hypercalcemia)
Advanced stage
- •Difficulty standing or moving
- •Prostration, excessive sleeping
- •Irritability or marked behavioral changes
- •Breathing difficulty; pale or bluish gums
- •Trembling, unusual vocalizations
When to seek immediate help?
These signs indicate a veterinary emergency. Contact your veterinarian or the nearest emergency clinic immediately:
- Respiratory distress: open-mouth breathing, heavy panting at rest
- Unable to stand, sudden collapse
- Blue gums or tongue (cyanosis): severe oxygen shortage
- Uncontrollable vomiting or diarrhea
- Extreme pain: intense vocalizations, unable to find a comfortable position
How is the diagnosis made?
An accurate diagnosis is essential before starting any treatment. Biopsy is the gold standard; it distinguishes lymphoma types and refines the prognosis.
Important: do not start corticosteroids before a definitive diagnosis. Steroids can alter the tumor response and compromise biopsy reliability.
History and physical exam
Abdominal palpation and superficial lymph node assessment, weight and general condition evaluation. Full history: symptom duration, progression, medications.
FeLV and FIV testing
Systematic screening for feline viral diseases: FeLV+ or FIV+ status influences prognosis and guides treatment choices.
Blood and urine tests
CBC, biochemistry, renal and liver function, calcium level. Hypercalcemia is sometimes associated with mediastinal lymphoma.
Imaging
Chest X-rays (pleural effusion), abdominal ultrasound with organ aspiration if needed, CT scan or MRI for certain locations.
Biopsy and advanced testing
Tissue sampling from a lymph node, intestinal segment, or affected organ. Histopathology + immunophenotyping (B or T cells) to determine grade and prognosis. Bone marrow examination if marrow involvement is suspected.
Treatment and management
Chemotherapy is the reference treatment. Cats generally tolerate it better than humans; side effects are often mild and manageable. The approach is tailored to the lymphoma type, grade, and the cat's overall condition.
Pain and supportive care
Multimodal pain management, nutritional monitoring, and having rescue medications on hand (anti-nausea, anti-diarrheal) are essential to ensure comfort and optimize quality of life throughout treatment.
What to expect?
Feline lymphoma is generally not considered curable in most cases; the goal is to achieve remission and maintain the best possible quality of life. Histological grade (low, intermediate, high) is one of the most decisive factors.
Multi-agent chemotherapy
Chlorambucil + prednisolone
Steroids only
A personalized treatment plan discussed with your veterinarian and ideally a veterinary oncologist is the best path to optimize both survival and your cat's well-being.
Home management tips
Comfort adaptations
Daily actions
- Strictly follow the treatment protocol and all follow-up appointments
- Keep a daily journal: appetite, weight, stools, vomiting frequency, behavior
- Minimize stress: reduce noise, commotion, other animals if needed
- Monitor weight and adjust diet in consultation with your veterinarian
- Keep rescue medications on hand (anti-nausea, anti-diarrheal)
- Proactively manage pain: report any sign of discomfort to your vet
- Consult a veterinary oncologist for an optimized treatment protocol
Avoid these
- Starting steroids before a definitive diagnosis: risk of altering tumor response and compromising biopsies
- Giving supplements or alternative medicines without veterinary approval: possible interactions with chemo
- Stopping a treatment protocol without prior consultation
- Smoking near your cat: demonstrated link with gastrointestinal lymphoma
- Ignoring even minor distress signs during active treatment
Always maintain
- Vaccinations and preventive care up to date (including FeLV for at-risk cats)
- Regular follow-up with veterinarian or oncologist
- Up-to-date identification (microchip)
Frequently asked questions
My cat is losing weight and vomiting regularly; could it be lymphoma?
What is the difference between low-grade and high-grade lymphoma?
My cat is FeLV-positive; can lymphoma still be treated?
Will chemotherapy make my cat very sick?
Why can't we just start steroids right away?
My cat is elderly; is it still worth treating?
This guide is provided for informational and educational purposes only. It does not constitute veterinary medical advice and is not a substitute for a consultation with a qualified veterinarian. Every animal is unique; their health must be evaluated individually. If you have concerns about your cat's health, contact our clinic or consult a veterinarian promptly.
Is your cat losing weight or vomiting frequently?
Our veterinary team can perform a full workup and guide you toward the treatment options best suited to your situation.