ABSTRACT: Cancer is a generic term encompassing different disease entities with similar pathology but potentially different outcomes. Surgery, radiotherapy and chemotherapy are all viable treatment options. Veterinary nurses [VNsI play a central role in helping manage cancer patients and it is important that the VN has sufficient knowledge and understands the individual treatment options prescribed. This information is invaluable when providing client care instilling owner confidence in the personnel treating their pet. This article discusses use of chemotherapeutics. highlighting potential health and safety implications and the role of the VN in treatment.

Use of chemotherapy

To prescribe appropriate treatment the veterinary surgeon (VS) must first reach a diagnosis. Possible diagnostic tests include fine-needle aspirates or biopsies of any masses, endoscopic biopsies, for example, of the gastrointestinal (GI) system and radiographs for diagnosis of bone tumours.

Once a diagnosis of cancer is achieved, the disease is then graded – this means that the VS looks at how aggressive the cancer is. High-grade (very aggressive) cancer grows quickly, invades the area directly around the tumour and is likely to spread to other body parts through metastasis.

When it has been graded, the cancer is then ‘staged’ according to the progression of the disease. The VS takes into account the size of the tumour, the number of masses and if the cancer has metastasised, in order to allocate a stage. Late-stage cancer is far advanced and is likely to be more difficult to treat effectively.

The VS will then choose a treatment option based on the nature, grade and stage of the disease, which may involve surgical excision of a mass, radiotherapy or chemotherapy. Chemotherapy may be employed as a cytoreductive treatment to reduce tumour size prior to surgery, or it may be a palliative treatment option in that it might not completely cure the disease but simply ease clinical signs and achieve a period of remission.

There are many different chemotherapeutic agents available and a selection of commonly used ones are summarised in Table 1.

Health and safety considerations

Prior to the use of chemotherapeutics in practice, full risk assessments must be carried out and standard operating procedures completed. Any storage areas for cytotoxic drugs must be clearly labelled to avoid accidents (Figure 1).

Figure 1: Any area where cytotoxic drugs are stored must be clearly labelled

Members of staff involved in administering chemotherapy must have sufficient training prior to undertaking the task. They must be aware of risks to personnel and wear the correct personal protective equipment (PPE) as detailed in Figure 2.

Figure 2: Staff must be aware of the risks and wear the correct personal protective clothing |PPE) or equipment

The VS who is responsible for preparing the drug – and wearing full PPE – handles the drug in a fume cupboard (Figure 3). All syringes and infusion bags are clearly labelled with the patient name, drug and dosage to ensure no confusion.

Figure 3: Chemotherapeutic drugs must be reconstituted in a fume cupboard by the VS 

Alongside risks to staff, there are risks to the patient receiving the treatment. When placing a catheter for intravenous (IV) administration, the placement must be successful on first attempt, owing to the risk of extravasation. If more than one attempt is required, a different vein must be used.

An example of technique is illustrated in Figure 4. If any concerns are raised during administration, the VS should be made aware immediately and will initiate appropriate action. It is important for a VN to communicate concerns quickly because of the high risk of serious problems.

Figure 4a: After the cathter is placed a T-port is attached and the first piece of tape attaches the catheter to the leg

Figure 4b: The second piece of tape is twisted around the top of the T-port and attached to the leg. This 'anchors' the catheter

Occasionally, a patient is hospitalised for treatment. It is important that any staff coming into contact with cytotoxic patients are aware of how to handle them. Appropriate labelling of hospitalisation sheets and kennels is essential and gloves must be worn when giving treatments (Figure 5).

Figure 5: Clear labelling of kennels containing cytotoxic patients is essential

Bodily excretions are cleaned up and double-bagged for disposal by personnel who are wearing gloves. Contaminated bedding is incinerated. It is best to be overcautious when handling cytotoxic patients, owing to the high risk they represent.

Role of the VN

The VN plays a vital role in chemotherapeutic treatment. Responsibilities include administering prescribed medication, nursing hospitalised patients, and communicating with – and educating – owners.

Administering chemotherapy is a prominent aspect of the role of the VN – this is when knowledge of various agents is useful. If a drug is administered intravenously, a catheter with a T-port must be placed (Figure 4). The catheter is thoroughly flushed with saline before and after administrati
on to ensure patency.

During administration, the VN regularly checks for perivascular infusion, frequently occluding the flow by applying gentle pressure above the catheter, checking the infusion slows and monitoring the site for puffing/oedema or leakage around the cannula site.

This is of particular concern when administering cytotoxic agents that will cause necrosis and skin sloughing, as inadvertent perivascular administration may result in amputation if tissue damage is extensive!

Alongside administration of chemotherapy, supportive care of patients is essential. Analgesia may be required – non-steroidal anti inflammatories (NSAIDs) are a common option and can be used synergistically with other analgesics. For example, a patient with an osteosarcoma may be prescribed a bisphosphonate such as pamidronate (Novartis Pharmaceuticals) in combination with an opioid such as tramadol hydrochloride (Actavis UK). If there are infected lesions, antibiotics may be dispensed; and dietary alterations could help if the patient suffers from oral lesions or cachexia (weight loss and deterioration in their physical condition).

Occasionally, chemotherapeutics may cause nausea, in which cases anti-emetic agents may be required. Prior to administering treatment, it may be advisable to premedicate with an anti emetic agent such as maropitant (Cerenia, Pfizer Animal Health) or metaclopramide (Emeprid, Ceva Animal Health).

Anaphylactic reactions are an occasional adverse effect of chemotherapy administration. These reactions can be life-threatening, but may be avoided by administering an antihistamine, such as chlorpheniramine, prior to treatment with the chemotherapeutic agent.

Ensuring the client is aware of the extra support that may be required is important when considering treatment options.

Usually animals receiving chemotherapy are outpatients. It is important when the patient is discharged, that clients are asked to monitor for potential adverse effects and emphasis should be placed on contacting the VS immediately because the patients condition may deteriorate rapidly.

Common adverse effects include vomiting, diarrhoea and myelosuppression (decreased production of leucocytes).This occurs because the chemotherapy attacks rapidly dividing cells (one of the main properties of most cancer cells), which means it also harms cells which divide rapidly under normal circumstances. These include the GI tract and bone marrow.

Instructions must also be given to avoid direct contact with excreted bodily fluids for at least 72 hours, to wear gloves to handle these and double-bag for disposal. 

Case history

A 13-year-old, female, spayed was Kerry Blue terrier, diagnosed with transitional cell carcinoma ITCCl in her bladder and proximal urethra. Clinical signs on presentation were haematuria and nocturia, clinical examination was normal, haematology and biochemistry were unremarkable as were thoracic radiographs.

Abdominal ultrasound was conducted revealing thickened, irregular bladder wall and thickening of proximal urethra. The patient was anaesthetised for cystoscopy, which confirmed thickening of proximal urethra and the mucosa of the btadder had invanginations of vacularised soft tissue.

Traumatic biopsies, using a urinary catheter through the scope, were collected. Squash biopsies diagnosed TCC, histology samples confirmed this diagnosis.

Unfortunately, prognosis was poor despite treatment. Various options were considered but because the mass was occupying almost 90% of the bladder and involved the urethra, surgery was not an option. The owners opted for chemotherapy because the patient was coping well at that time.

The VS prescribed a course of mitoxantrone, given via IV infusion every 3 weeks, in combination with piroxicam [10mg per os every other day]. The owner was advised to monitor urine output and if nothing was produced in a 24-hour period, to contact the VS immediately as this could indicate obstruction. The owner was directed to avoid contact with bodily fluid for 72 hours after chemotherapy and to wear gloves to handle and double-bag for disposal.

The patient responded to the initial course of chemotherapy without any serious adverse effects and went into remission. Unfortunately, she relapsed five months later and is currently receiving a second course of mitoxantrone.


Laura Crump RVN

Laura joined Dick White Referrals shortly after qualifying in 2010 and works in the internal medicine department. She is currently studying for her Certificate in Anaesthesia and Critical Care and has started the Diploma of Advanced Veterinary Nursing in September. She has a particular interest in emergency medicine and oncology.

To cite this article use either

DOI 10.1111/j.2045-0648.2012.00175.x or Veterinary Nursing Journal Vol 27 pp 183-185

Useful references

FOALE. R. D.. DEMETRIOU. J (2010) Saunders Solutions in Veterinary Practice: Small Animal Oncology. Saunders Ltd HOTSTON MOORE. A . RUDD. S (2008) BSAVA Manual of Canine and Feline Advanced Veterinary Nursing. 2nd Edn BSAVA. Gloucester

Veterinary Nursing Journal • VOL 27 • May 2012 •