🐱 Veterinary Overview of Lymphoma in Cats: Diagnosis, Forms, and Treatment Options in 2025 🩺

By Dr. Duncan Houston, BVSc

🔍 What Is Lymphoma?

Lymphoma is the most common cancer in cats, representing nearly 30% of all feline malignancies. It originates from lymphocytes, which are a type of white blood cell critical to immune function. Since lymphocytes circulate throughout the body, lymphoma is rarely localized, making chemotherapy the main treatment rather than surgery or radiation alone.

📍 Types of Lymphoma by Location

Categorizing lymphoma by the area of the body it affects helps guide treatment and expectations. The most common types include:

• Intestinal lymphoma (most common form in cats)
• Renal lymphoma (affecting the kidneys)
• Nasal lymphoma (often localized)
• Mediastinal lymphoma (chest/lymphatic tissues)
• Multicentric lymphoma (multiple lymph nodes)

🦠 Intestinal Lymphoma

Often seen in senior cats aged 9–13, intestinal lymphoma presents with weight loss, vomiting, and diarrhea. Appetite may vary. It can appear as infiltrative disease or as masses in the bowel.

Diagnosis may involve:

• Surgical biopsy (full access, more invasive)
• Endoscopic biopsy (less invasive, good for mucosal layers)
• Needle aspiration (non-invasive, limited accuracy)
• Ultrasound (non-invasive, may suggest diagnosis)

Treatment: Most intestinal cases are low-grade and treated with oral medications such as prednisolone and chlorambucil. Remission rates are high, and survival times range from 23–30 months. High-grade types have a poorer prognosis.

🧪 Renal Lymphoma

This aggressive form affects the kidneys, often causing increased thirst, vomiting, and weight loss. Unlike typical kidney disease, affected kidneys are large, not shrunken. Diagnosis is often confirmed with ultrasound-guided aspirates.

Treatment: Chemotherapy can shrink tumors and improve kidney function temporarily, but the average survival is 3–6 months. Nervous system spread occurs in about 40% of cases.

🫁 Mediastinal Lymphoma

Affects central chest structures and causes fluid build-up, leading to labored breathing. Most cats with this form are under 5 years old and often FeLV-positive.

Treatment: Chemotherapy is standard, and while remission is achievable, FeLV-positive cats often face other complications that reduce survival time.

👃 Nasal Lymphoma

This rare form is potentially localized and presents with nasal swelling, sneezing, and discharge. Though localized, treatment usually includes chemotherapy, assuming possible systemic spread.

Prognosis: With treatment, survival can exceed 500 days.

📊 Grading and Prognosis

Lymphoma is graded based on how aggressive it appears under the microscope. High-grade lymphomas grow rapidly but may respond quickly to chemo. Low-grade types grow slower but achieve longer remissions—especially in intestinal forms.

💊 Treatment Overview

• 📋 Oral medications: Prednisolone + Chlorambucil (low-grade cases)
• 💉 Injectable chemotherapy: For high-grade or systemic involvement
• 🧬 Supportive care: Appetite stimulants, hydration support, regular monitoring

Cats generally tolerate chemotherapy well. Side effects are rare, and the main challenge is administering medication and regular vet visits.

📈 Summary of Key Stats (2025)

• 🧪 30% of feline cancers are lymphoma
• 📅 Average age of onset: 9–13 years
• ⏳ Remission with low-grade intestinal lymphoma: 23–30 months
• ⚠️ Renal lymphoma survival: 3–6 months
• 🧬 Mediastinal lymphoma: often FeLV-positive cats under 5

📱 Need Help with Diagnosis or Treatment Planning?

Visit AskAVet.com or use the Ask A Vet app to connect directly with licensed veterinarians. We’ll help you navigate lymphoma diagnosis and treatment options tailored to your feline friend. 🐾💙