Radiotherapy, or radiation therapy, is a medical process in which veterinary professionals use high energy radiation (normally x-rays) to achieve medical outcomes in many pets, including dogs. Just like in people, it has its uses, but also its risks.

Just as in human radiotherapy, the radiation causes damage to the inside of living cells by affecting the function of the DNA and its ability to synthesise small, useful proteins. Radiotherapy can be dangerous because it is not specific to cancer cells. And therefore has the same effect on healthy, useful body cells. But generally, cancer cells are much more sensitive to radiation than healthy cells. It can be used alone or in conjunction with other modes of treatment. Radiation therapy can be used to treat cancer or can be used as a palliative care method for cancers. It is commonly used for tumours which are localised, or in areas where anatomy makes surgical removal of the mass very difficult or impossible.

There are different types of radiation therapy available

The length of session and intensity of radiation will depend on many factors and will be specific to each case. Different types of cancers require different types of therapy. The veterinary professionals will need to perform testing such as fine needle aspirates, biopsies and blood panels in order to assess the type and stage of cancer present. Imaging techniques may need to be performed to look for any metastatic tumours (spread); and to assess the response to  medication too. It is important to follow the advice of veterinary professionals in order to learn how the patient is responding and what the prognosis is likely to be. Speaking to veterinary professionals will help to gauge how long therapy is likely to take in order to achieve the desired outcome. 

The two main types are radiotherapy using a beam of radiation, performed in a special operating room; or radiotherapy using radioactive materials injected into the tumour or the patient. This second type is much rarer in dogs than in horses or cats.

Deciding if a dog is suitable for radiotherapy

Pets who are to undergo radiation therapy will need to be well behaved in order to tolerate the procedures involved. They will be required to stay still for a period of time, and this must be repeated multiple times. 

The dog must be fit to travel and happy to do so. As well as not being too stressed within a veterinary practice environment. Because not all veterinary practices offer radiation therapy, a referral to another practice that does offer it may be needed. This could include travelling further. Please speak to your local veterinary practice about where the closest or most suitable place to receive this treatment may be. 

Pets receiving this treatment protocol often need to be sedated or put under a general anaesthetic in order to receive the therapy; which is high risk in critically ill patients. This makes it vital that the veterinary professionals assess the pet’s general health profile as well as the cancer.

Side effects are possible

As with all treatment protocols, there are side effects which a pet may experience. These include a loss of hair, darkening of the skin, inflammation, or loss of elasticity from the area in which the radiation is targeted. In rare cases, some animals will suffer from delayed side effects. These could occur months or years after the therapy has actually finished. These include fractures, non-healing wounds or new tumours growing – but they are very rare.

Unlike in humans, severe sickness and hair loss are rare, and would usually result in a change of protocol, if they couldn’t be controlled. Veterinary professionals will do everything they can to minimise risks. They will treat any side effects with medication appropriately to keep pets as comfortable as possible throughout the treatment and during the recovery period.

The cost of radiotherapy can be very high

A course of radiotherapy takes place over a long period of time; which requires commitment and dedication to the treatment plan. If your pet requires radiotherapy, ensure you speak to your insurance company regarding your cover. And check if they are happy to pay for it prior to starting treatment if it is something you otherwise will not be able to afford.

Radiotherapy is available for dogs, although it isn’t suitable for every dog, or for every type of cancer. But it does give us extra options if we need them!

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