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The Chemotherapy Team     

In the 16 years since the Oncology Service established a dedicated chemotherapy treatment centre, the team has helped to treat many cats and dogs with cancer. The number of cases coming through has increased year-on-year since the centre was established.

In December 2024, the team moved into a new chemotherapy treatment room, which enables even more animals to be treated and cared for in a comfortable, relaxed environment.

Chemotherapy drugs can also be used to treat other diseases, so in addition to animals under the care of the Oncology Service, some patients from the Neurology Service also benefit from treatments in the purposely designed new area.

There are typically between 20-25 dogs and cats in total having chemotherapy delivered by the Oncology and Neurology ÐÂÔÂÖ±²¥ in any given week. We share a small selection of cases treated and cared for across a working week below.

Benefits of the new room include:

• A quiet space for treatment: The new room offers a calm environment away from the busy hospital, ensuring pets feel more comfortable and relaxed during treatment.
• Reduced infection risks: Since chemotherapy patients often have weakened immune systems, keeping them in a dedicated space lowers the risk of exposure to other areas of the hospital and conditions.
• Helping more animals: With the extra space, the oncology team can treat more patients.
• Improved welfare: Separate treatment rooms for dogs and cats enhances the wellbeing of all our patients.
• Helping owners: Pets now have a quiet room to rest in while waiting to be picked up, providing greater flexibility and peace of mind for clients.

Monday   

Mathilda, an 11-year-old cat, initially presented to the Emergency and Critical Care Service for further investigations into a marked hyperglobulinaemia, anaemia and lethargy. Following extensive diagnostic testing, Mathilda was diagnosed with multiple myeloma (MM).

MM is a systemic proliferation of malignant plasma cells or their precursors. The treatment of MM is systemic chemotherapy, in cats usually with cyclophosphamide (administered once every 2-3 weeks) combined with prednisolone. Most cats (50%–80%) respond favourably to chemotherapy, although the durability of response tends to be shorter when compared to dogs, with median survival times (MST) reported as 4-13 months.

At time of diagnosis, Mathilda’s globulin count was raised (74.7g/L), after commencing treatment, her disease went into remission, and her globulins returned to normal within a month. Unfortunately her remission was short, as six weeks later her disease progressed so her chemotherapy was changed to melphalan, but due to persistent neutropenia, Mathilda’s treatment was again switched to chlorambucil. She has been in remission since.

To facilitate treatments, Mathilda initially required intra-muscular sedation for her visits. However, in time, and with her owners help, the team found a method that suited her better. Before each visit, Mathilda received gabapentin orally at home two hours before her appointment and topical anaesthetic cream was applied over her vein, 30 minutes before blood sampling. This combination allowed for smooth venepuncture, without the need for further sedations and a longer hospital visit.

Mathilda continues to receive oral chlorambucil at home, given by her owner, and requires a check-up and blood test every 6-8 weeks at her local practice.

Tuesday     

Alan is a seven-year-old miniature dachshund. Alan’s family always wanted a dog named Alan and so she was named accordingly, despite being female.

She initially presented to the RVC with a six-week history of hyporexia, polyuria-polydipsia, weight loss (2 kg), snoring, difficulty in swallowing, lethargy and vomiting. Clinical examination revealed pyrexia, enlarged tonsils and peripheral lymphadenopathy. Following extensive diagnostic testing, Alan was diagnosed with intermediate-sized T-cell peripheral nodal lymphoma, stage V (circulating neoplastic lymphocytes), substage b, with paraneoplastic hypercalcemia.

Alan was treated with a modified LOPP protocol (vincristine, lomustine, procarbazine and prednisolone) and went into complete remission. After five months, chemotherapy had to be discontinued as she developed persistent thrombocytopaenia as a side effect, which later resolved.

It is two years since Alan completed her chemotherapy protocol, and she remains in complete remission, regularly returning for clinical re-assessment (measuring lymph nodes) every three months, to check that she remains well.

Alan was nervous and demonstrated aggressive behaviours when she first presented to our service and extreme caution was taken on her handling for our safety. However, over time she came to enjoy cuddles and fuss, not to mention treats. We used topical anaesthetic cream at every visit and she became far less reactive to blood sampling and IV catheter placements.    

Wednesday     

Pooh is an eight-year-old, diagnosed with squamous cell carcinoma on his nasal planum. Three weeks after his first electrochemotherapy (ECT) he was presented for a second, follow-up treatment. However, examination showed a complete response and repeat ECT was therefore not required, so Pooh got to enjoy the quiet and luxury of the chemotherapy treatment room for a short time!

Several treatment options had been discussed for Pooh, including ECT, surgical resection and radiation therapy. ECT is usually our first choice as it is less costly, it usually results in very satisfactory aesthetic outcomes and often achieves good results, with long-term control. It involves the administration of a chemotherapy drug (bleomycin) together with electric pulses to the site of the tumour, which enhances the transmembrane delivery of the drug and kills the cancer cells.

Complete resolution of the lesion is reported in 77%-82% of cases. Responses can be very durable in case of a complete remission, with only 2 out of 11 patients with complete remission showing relapse in one study.

Thursday    

Bandit, a nine-year-old cat, presented to our Internal Medicine Service for further investigations into precursor-targeted immune-mediated anaemia (PIMA), which was later identified by clonality testing as being a secondary condition to hepato-splenic lymphoma.

Bandit received multiple blood transfusions to try to improve his anaemia, whilst the team investigated the reason why he wasn’t responding to treatment. Each transfusion allowed a brief improvement in his condition but were short-lived. At the point of cancer diagnosis, his PCV was 11%.

Once a diagnosis of cancer was made, Bandit started chemotherapy treatment (cyclophosphamide, prednisolone and vincristine) and he quickly showed significant clinical improvement.

Bandit finished a total of five months of treatment and he is now being monitored every two to three months with bloods at his primary care practice.

Friday     

Saoirse, an eight-year-old Irish water spaniel, was diagnosed with high-grade B-cell peripheral nodal lymphoma – minimum WHO stage IIIa after being presented with enlarged lymph nodes, but was otherwise well (substage a).

Chemotherapy is the mainstay treatment for lymphoma in dogs. Approximately 90% of dogs with peripheral nodal lymphoma will go into remission when treated with a six-month, multi-drug chemotherapy protocol. The CHOP protocol involves weekly visits where either vincristine, cyclophosphamide or doxorubicin chemotherapy is administered alongside prednisolone as a rolling cycle.

The MST is 10-12 months for B-cell peripheral nodal lymphoma, with approximately 10-20% of patients living two years or longer, however some animals, unfortunately, have resistant cancers and respond for shorter periods of time or do not respond at all.

Saoirse is currently receiving her CHOP protocol and has shown a really positive response to treatment, remaining in clinical remission since November, so we will continue to see her regularly for a while longer.

The new chemotherapy treatment room was supported by the RVC’s registered charity, the Animal Care Trust.