What is Canine Cancer?

Just like humans, dogs are made of trillions of cells and, just like humans, canine cancer is caused when old or abnormal cells reproduce (7).

Many naturally-occurring cancers that affect humans also affect dogs (5). In fact, canine cancer has long been established as a strong comparative model for cancer in humans (1,2,3,4). As dog tumours are histologically similar to human tumours, they respond similarly to conventional therapies (6).

The primary reason for the proliferation of canine tumours that are similar to human tumours is the fact that dogs are fully immersed into our human environment – they eat similar foods and are exposed to similar risk factors (8–12). Effectively, their connection to our human world is the central reason why more dogs are affected by cancer than any other animal.

What Causes Cancer?

Cancer can be defined as abnormal cell growth caused by changes in the genes, which act as the instruction manual for how cells are made and how healthy they’ll be. Therefore, when genes express unhealthy traits, they begin to produce unhealthy cells, which causes a change in gene expression.

The graph below shows the factors that play a role in the development of cancer. Although this is a chart about human cancer, we can also use it to predict why our dogs are suffering because of the fact that canine cancer is comparable to human cancer.

As you can see, cancer is overwhelmingly caused by unhealthy lifestyles and harmful environments. The fact that only 5–10% of all cancer cases are caused by genetic flaws and the remaining 90–95% are caused by environmental and lifestyle factors provides us with significant opportunities to prevent cancer (14).

How do Unhealthy Lifestyles and Harmful Environments Lead to Cancer?

The answer can be found in epigenetics – the study of the ways in which our behaviours and environments affect our genes.

Ultimately, the quality of the lifestyle and environment that our dogs experience will determine their likelihood of cancer. The more natural their lifestyle, the more likely they’ll express healthy genes and create healthy cells. The power of epigenetics has been evidenced in plenty of animal model studies (14-18).

As you can see from the graph, diet is the biggest determinant of cancer. This has been confirmed by many studies that have highlighted how diet can contribute to chronic inflammation, obesity, and calorie excess. This negatively affects DNA, increases DNA damage, and causes epigenetic alterations that increase the risk of cancer(19).

The good news, however, is that epigenetic alterations are reversible.

What is an Anticancer Diet?

A growing number of preclinical and clinical studies report that dietary intervention through a ketogenic diet is a powerful anti-cancer therapy that can be safely applied for canine cancer (20-24). A ketogenic diet is a low-carbohydrate, high-fat diet that mimics certain characteristics of fasting. As cancer feeds on glucose, the ketogenic diet creates an unfavourable metabolic environment for cancer cell proliferation, which effectively starves the cancer.

Another process that is affected through diet is angiogenesis – the formation of new blood capillary vessels that provide expanding tissues, organs, and tumours with oxygen and nutrients while removing metabolic waste. Deregulated angiogenesis plays an essential role in feeding tumour growth (25). Certain foods, however, prevent angiogenesis, which effectively starves the cancer (26).

Therefore, an anticancer diet can be described as a ketogenic diet that incorporates ingredients that inhibit angiogenesis.

Is an Anticancer Diet Right for your Dog?

Firstly, a holistic approach needs to be taken to cancer. Try to remove all possible contributing factors that surround your dog. Chemical cleaning products, second hand smoke, polluted areas etc. However, the most important and influential factor that will need to change is your dog’s diet.

I would also like to add, this depends on the age of the dog and whether you feel there’s more life left. I wouldn’t pushed a dramatic dietary change upon an really elderly dog, it may be better to just live their best life possible. However, you can try implement as much of this as you like.

Second, the extent to which you implement an anticancer diet guidance will also depend on the age of your dog. For example, I wouldn’t push a dramatic dietary change upon an elderly dog, as it may be better for them to continue their routine and live the best life they possibly can.

It’s also worth remembering that a holistic approach should always be prioritised. Therefore, in addition to dietary changes, you should also try to remove all other possible contributing factors, such as chemical cleaning products, second-hand smoke, and polluted areas.

Diet Breakdown

Protein

A medium protein diet is recommended. This is because you’ll need a high-fat diet to replicate a ketogenic diet and, if your dog’s dietary protein is too high, it’s likely the meat you’re using is too lean.

Fat

A high-fat diet made up of between 20–30% fat is recommended.

Carbohydrates and Fibres

All carbohydrates and gluten should be completely avoided. Anti-cancer ingredients such as broccoli and cauliflower should constitute 10–15% of your dog’s diet. Herbs such as parsley are also highly recommended for their anti-angiogenic propensities.

Vitamins and Minerals

A complete meal daily is recommended, as studies have shown that both restricted and exaggerated mineral intake can increase the risk of cancer progression (27).

Recommended Supplements

Cordyceps/Turkey Tail Mushrooms: Mushroom polysaccharides with immunomodulation and anticancer effects (28).

Genistein: A natural flavonoid reported to exhibit anticancer effects (29).

Resveratrol: A stilbenoid that activates natural killer cells and inhibits cancerous cell growth (30).

Quercetin: A flavonoid that is highly toxic against cancerous cells (31).

References

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3. Nat. Biotechnol. 24, 1065–1066. (doi:10.1038/ nbt0906-1065b)
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24. Leung, Y.B., Cave, N.J., Heiser, A., Edwards, P.J., Godfrey, A.J.R. and Wester, T., 2020. Metabolic and immunological effects of intermittent fasting on a ketogenic diet containing medium-chain triglycerides in healthy dogs. Frontiers in veterinary science, 6, p.480. https://www.frontiersin.org/articles/10.3389/fvets.2019.00480/full
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28. Singdevsachan, S.K., Auroshree, P., Mishra, J., Baliyarsingh, B., Tayung, K. and Thatoi, H., 2016. Mushroom polysaccharides as potential prebiotics with their antitumor and immunomodulating properties: A review. Bioactive carbohydrates and dietary fibre, 7(1), pp.1-14.
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Should we offer some guidance on what people can do if their dog does have pancreatic cancer?