ALL SPECIES · Condition guide
Lymphoma in dogs and cats: real veterinary cases
Lymphoma is a cancer of lymphocytes. In dogs, the most common form is multicentric — enlarged painless lymph nodes felt under the jaw, in front of the shoulder, and behind the knees. In cats, alimentary lymphoma (gut) is the most common form and looks like chronic vomiting, weight loss, or diarrhea — easily mistaken for IBD.
Lymphoma is one of the few cancers in pets that responds well to chemotherapy. Multi-drug CHOP protocols achieve remission in around 80% of B-cell canine lymphoma cases, with median survival around 12 months. T-cell forms and feline gastrointestinal lymphoma have different prognostic profiles, so subtyping is essential.
What vets typically check for
- Fine-needle aspirate of an enlarged lymph node — often diagnostic on cytology.
- Flow cytometry or PARR (PCR for antigen receptor rearrangement) to subtype B vs. T cell.
- Staging: CBC, chemistry, abdominal ultrasound, +/- thoracic radiographs.
- Treatment: CHOP protocol (Cyclophosphamide, Doxorubicin, Vincristine, Prednisone) over ~6 months.
- Cats with gastrointestinal lymphoma: confirm via endoscopic or full-thickness biopsy first.
Not a replacement for veterinary care. Use this to walk into the conversation prepared, not to self-diagnose.
Real cases from the veterinary literature
Peer-reviewed reports our semantic search surfaces for Lymphoma. Click into any case for the full abstract — or run a personalised search with your pet's exact details.
- Large-cell lymphoma in four cats after successful treatment of feline infectious peritonitis with oral GS-441524: a novel clinical observation
Journal of Feline Medicine and Surgery · 2026 · GB
Four cats developed large-cell lymphoma (LCL) after being successfully treated for feline infectious peritonitis (FIP) with an oral medication called GS-441524. These cats, ranging from under 2 years to 13 years old, showed symptoms like weight loss, decreased appetite, and chronic vomiting. They were diagnosed with LCL between 81 and 595 days after their FIP treatment, and sad
- Abstract 7913: OXC-101 (karonudib) in canine lymphoma and hemangiosarcoma: Safety, early efficacy, and translational potential
Cancer Research · 2026
A group of nine dogs with aggressive cancers, specifically lymphoma and hemangiosarcoma, were given a new oral treatment called OXC-101 (karonudib) to see how well it worked and if it was safe. Most of the dogs had previously received chemotherapy and showed some improvement, with stable disease or partial responses lasting up to five months. One dog with untreated lymphoma had
- Diagnosis of pyogranulomatous and neutrophilic lymphadenitis in 72 cats presenting to a referral hospital: with a focus on nine cats with steroid-responsive lymphadenitis.
Journal of feline medicine and surgery · 2026 · United Kingdom
A 7-year-old male cat was brought to the vet with symptoms like lethargy, loss of appetite, fever, and swollen lymph nodes. After testing, the diagnosis was steroid-responsive lymphadenitis, a condition where the lymph nodes become inflamed without a clear cause. The cat was treated with prednisolone, a steroid medication, and showed improvement initially, but some cats may rel
- Distribution of neoplasia in Danish cats: data from the Danish Veterinary Cancer Registry.
Journal of feline medicine and surgery · 2026
A study of Danish cats found that many are diagnosed with cancer, with 767 cases recorded between 2005 and 2023. Most of these tumors were malignant, particularly affecting the skin and mammary glands, and female cats were more commonly diagnosed than males. The average age of affected cats was about 10 years. Notably, intact female cats had a higher risk of developing mammary
- Computed tomographic evaluation of canine hepatic lymph nodes: Establishment of aorta-normalized dimension ratio cutoff values for differentiating normal from abnormal conditions
Veterinary World · 2026 · NZ
A study looked at 84 dogs who had abdominal CT scans to check their liver and surrounding organs. The researchers measured the size of the hepatic lymph nodes (HLNs) and found that those with organ problems had significantly larger HLNs compared to healthy dogs. They established size ratios based on the aorta, which can help veterinarians identify potential issues in the liver,
- A potential risk factor associated with acute tumor lysis syndrome in dogs with multicentric lymphoma receiving chemotherapy.
Journal of veterinary internal medicine · 2026 · Japan
A group of 24 dogs with high-grade multicentric lymphoma received chemotherapy, and some developed acute tumor lysis syndrome (ATLS), which can cause serious health issues like kidney problems. In this study, 5 dogs showed laboratory signs of ATLS, while 2 had clinical symptoms. The risk of developing ATLS was linked to factors like receiving a specific chemotherapy drug (L-asp
Frequently asked questions
- Is chemotherapy hard on dogs and cats?
- Veterinary chemotherapy is dosed for quality of life, not maximum tumour kill — most dogs and cats tolerate it remarkably well. The vast majority continue normal activities throughout treatment, with only occasional brief GI upset or mild fatigue.
- What's the prognosis without treatment?
- Untreated, most dogs with multicentric lymphoma survive 1-2 months. With prednisone alone, ~2-3 months. With CHOP chemotherapy, median survival is around 12 months and ~25% reach 2 years. Treatment changes the trajectory substantially.
- Is lymphoma curable?
- Curative outcomes are uncommon — most lymphomas eventually relapse and become drug-resistant. The realistic goal is high-quality remission, often for a year or more. Some indolent forms (e.g. T-zone lymphoma) behave much more like chronic disease.