Cancer is not a word that any of us wants to hear when we take a beloved pet to the vet.
But according to the Animal Cancer Foundation, one in every four dogs will develop cancer in his or her lifetime
Veterinary medicine, like human medicine, has made progress in treating this disease. And there are now a range of options for many dogs diagnosed with cancer.
We’ll take a look at these in this article, and discuss ways of reducing the odds of your puppy developing cancer some time in the future.
What Is Cancer In Dogs?
In simple terms, cancer occurs when the ability to ‘switch off’ cell division has failed.
Cells are the building blocks from which our organs and bodily tissues are constructed. And there are times when it is important for cells to multiply – during growth or tissue repair for example.
Much of the time, rapid multiplication of cells is inappropriate. Which is why we need that important ‘off switch’
Causes Of Cancer In Dogs
We know a lot about what causes cancer, and many substances have been identified which have carcinogenic (cancer causing) properties. Examples we are all familiar with in people are cigarette smoke, and radiation.
Some hormones are known to be linked with cancer too. We know that neutering dogs at a very young age for example can reduce the risk of some cancers, and that it may increase the risk of others. But there is still much we have to learn.
We also know that cancer in dogs isn’t just associated with exposure to environmental triggers. The disease has a hereditary element too.
Some pedigree breeds of dog are more likely to get certain types of cancer, than other breeds, or crossbreeds.
In many cases we are not sure exactly how this works, though we do know that genes must be involved somewhere. And that limiting the gene pool within individual breeds will have made things worse.
In some breeds cancer is a significant factor in longevity.
But whilst we know that flat-coated retrievers for example are prone to cancer, we don’t yet have a DNA test to enable us to make better breeding decisions, or to elimate cancer carriers/affected dogs from our breeding stock.
Other examples of susceptible breeds are Boxers, Bernese Mountain Dogs, Boston Terriers, and Golden Retrievers.
Different breeds may be prone to different types of cancer, and it is important to be aware of the signs and symptoms of cancer, especially if you have a dog from a breed that is particularly at risk
Cancer In Dogs Symptoms
Treating cancer successfully hinges on a number of factors, including the type of cancer you are dealing with.
An important factor is of course early detection and treatment.
Dogs aren’t always able to let us know that they are unwell. But there are a number of signs of cancer in dogs that we can look out for. Indications that something is wrong and that the dog should be examined by a vet without delay.
The national Canine Cancer Foundation has put together a list of ten cancer in dogs symptoms to look out for
- Abnormal swellings that persist or continue to grow
- Sores that do not heal
- Weight loss
- Loss of appetite
- Bleeding or discharge from any bodily opening
- Offensive odour
- Difficulty eating or swallowing
- Hesitation to exercise or loss of stamina
- Persistent lameness or stiffness
- Difficulty breathing, urinating or defaecating
If your dog displays any of these symptoms, he needs to see a veterinary surgeon
Diagnosing Cancer In Dogs
Once your vet has examined your dog, he may need to remove all, or a part of any lump or suspected tumour and send it away to a laboratory for analysis.
In some cases he will take a small sample of tissue using a needle.
Once he gets the results back from the lab, he’ll be able to tell you exactly what the tumour (lump) is and whether it is malignant (cancerous).
He’ll then be able to give you a prognosis. In other words, he’ll tell you what he expects to happen next, and how good your dog’s chances are of making a complete recovery.
Dog Cancer Treatment
If there is something nasty growing inside your dog, you’ll want to see it removed as soon as possible.
Where possible, an important treatment for a malignant tumour is to surgically and permanently remove it.
Just like human cancer patients, dogs can be treated with chemotherapy and/or radiotherapy.
Whether or not this may be appropriate for an individual dog will be something that may be discussed between the dog’s owner and veterinary surgeon.
Avoiding Cancer In Dogs
The fact that some breeds of dog are more likely to get cancer than others, may influence your choice of breed when you search for a puppy.
The following breeds that have a lower cancer rate than average (source)
- Irish Setters
- Jack Russell Terriers
- Rough Collies
- Yorkshire Terriers
There are also procedures that reduce the risk of certain cancers.
Neutering, especially at a very young age, interferes with your dog’s hormone levels and may influence the development of certain tumours.
You can for example, reduce your female dog’s risk of mammary cancer by having her spayed before her second season.
Spaying before the first season almost entirely eradicates the risk of mammary cancer, but there are disadvantages to a very early spay, so you need to talk to your vet about the pros and cons.
If your vet says there aren’t any cons, you might want to consider another opinion, as the latest evidence suggests this is not the case.
Neutering a male dog, fairly obviously, removes the risk of testicular cancer, but this is not a particularly common cancer in dogs. And the procedure may increase the risk of some other types of cancer.
Again, this is an issue to discuss with a vet who is up to date on the latest evidence with regards to neutering.
Dog Cancer Diet
Unfortunately there have not yet been any clinical trials or studies on the effects of diet on the incidence of cancer in dogs.
We don’t know for example, whether a natural raw diet might reduce the risk, though we do know that some cancers may be dependent on glucose for their growth. So feeding a diet high in fat and low in sugars may help.
We know too that obesity is associated with cancer in humans, so it makes sense to keep your dog slim.
We also know that regular exercise is a significant factor in longevity in humans, and there is no reason to think that dogs may not be affected similarly.
Bearing in mind the all round benefits of exercise, it is therefore well worth making sure your dog gets regular exercise sessions too.
Cancer In Dogs
If you pick a breed of dog that is not overly susceptible to cancer, this will reduce your risk of having to deal with this unpleasant disease in your four legged friend.
Keeping him slim and well exercised will improve his chances of staying in good overall health, and may reduce his risk of cancer too.
Apart from avoiding exposure to well known carcinogens such as cigarette smoke, there is not a great deal more you can do in the way of lifestyle changes, that will definitely reduce your dog’s risk of getting a tumour.
Keep in regular contact with your vet, especially as your dog ages, report any changes that you find promptly, and your dog should have the best chance you can give him of a long and healthy life.
More Information and Resources
- ASPCA information on canine cancer
- The Dog Cancer Blog
- Epidemiological studies of risk factors for cancer in pet dogs
- Animal cancer foundation