Unfortunately, just like humans, sometimes our pets will develop cancer. Roughly a quarter to a third of all patients will suffer from cancer at some point in their lifetime.
Cancer is caused when some of the billions of cells that form a living individual stop obeying the strict rules of behaviour that they normally follow in regards to cell growth rate, the rate at which they die and the degree to which they migrate.
Cancer is the process when cells may grow too fast, fail to get old or die at the right time, invade neighbouring tissue and move to other parts of the body and grow there. The cells may produce chemicals that make the animal feel ill and have effects on other parts of the body, such as the immune system which helps to fight disease.
We often use the terms ‘cancer’ and ‘tumour’ interchangeably, however, the term ‘cancer’ generally indicates the presence of a tumour with malignant behaviour. It important for owners to be aware that there are many different types of cancer, it is not a single disease and varies widely between patients.
What are the signs my pet may have cancer?
There are multiple different signs that may mean that your pet might have cancer, although always be aware that many of these signs can also be caused by other conditions. It is key for owners to visit with their pet for a physical examination if they become aware of any abnormalities, as they would normally with any sign of ill-health.
Possible clinical signs:
- An abnormal swelling or mass
- Loss of weight, despite a healthy appetite
- Loss of appetite
- Exercise intolerance
- Struggling to pass urine or faeces
- Bleeding from any orifice
- Difficulty eating or swallowing
- Persistent lameness
How is cancer diagnosed?
During your initial consultation, your vet will perform a full physical examination. Often if a mass or abnormal swelling is present a sample will be taken from it to allow assessment of abnormal cells. Biopsies may also be taken from nearby lymph nodes. Other investigation may include blood tests and diagnostic imaging such as X-rays or ultrasound to assess for the spread of the disease. Sometimes animals will require different types of imaging such as CT or MRI scans, if this is the case then your pet will be referred to see a veterinary oncology specialist with these facilities.
What are the normal treatments for cancer?
There are 3 main types of treatment for cancer:
- Surgery: the surgical removal of the cancer cells
- Chemotherapy: the use of drugs to kill cancer cells within the body
- Radiation: The use of ionizing radiation to control or kill cancer cells.
The best type of treatment depends on the type, location and extent of the cancer as well as the overall health of the patient. Some cancers have multiple methods of treatment. Our main concern is to try and maintain and improve patient’s quality of life and this is done by tailoring treatment to the patient and owners’ expectations.
Chemotherapy is the use of drugs to treat cancer. Sometimes it is used in conjunction with other forms of treatment such as surgery or radiation therapy.
The drugs used to interfere with the ability of cells to grow and multiply. Unfortunately, these drugs can’t discriminate between healthy cells and cancer cells, especially those of the bone marrow and gastrointestinal tract. Healthy cells, however, are better able to recover and repair themselves than cancer cells.
Most chemotherapy drugs are given either by mouth or via injection, often into the vein but sometimes into the muscle or under the skin. In some cases, the most effective treatment is the use of multiple drugs working in different ways to kill the cancer cells.
Chemotherapy is used in veterinary medicine to prolong an animal’s life and most importantly to try and improve their quality of life. While humans and animals receive many of the same drugs for chemotherapy, we do not use the high doses seen in intensive human protocols. This often means that animals face much-reduced side effects.
How long will my pet receive chemotherapy for?
The duration of treatment and number of treatments is dependent on the type of cancer being treated, and how well the patient is tolerating treatment. Treatment may be given daily, weekly or monthly, it can also be given in cycles which include rest periods.
Are there risks of exposure to the drugs?
- We advise that all oral drugs are kept out of the reach of children. While most oral drugs have a protective coating, we recommend the use of gloves when administering medication and to never split or crush tablets.
- It is important that owners avoid any unnecessary contact with urine and faeces of animals receiving chemotherapy, especially for the first week after treatment. This may involve wearing gloves to pick up waste, or if an animal has an accident inside ensuring that surfaces are thoroughly cleaned.
Will my pet have side effects?
We will always try to ensure sure we choose the drug dosages and combinations that have the least number of side effects while still giving the best therapeutic effect. We will always discuss any possible side effects with you prior to starting any chemotherapy treatment protocol.
Possible side effects include:
- Hair loss
We always recommend you watch your pet closely, following chemotherapy and contact us immediately if you have any concerns.