Our pets now live longer, so it’s more likely they’ll develop cancer

Q: My last three pets were diagnosed with cancer of different types. I know they were old (my cat was 19!) but it seems so wrong that they would all die this way. Is it my imagination or are cats and dogs getting cancer more often than the used to?

Dr. Patty Khuly has a veterinary practice at Sunset Animal Clinic in South Miami.

A: It’s a fact: If we’re lucky to live long enough, we’ll all get cancer. It’s just how aging mammalian cells fail. Mistakes in the repair mechanism of cells, many of them genetically preprogrammed, will lead to a failure of proper self-editing. Affected cells will lose their normal control mechanisms and the new tissues they comprise will grow abnormally.

What I’ve described is an oversimplification, of course, but one that finds many of my clients feeling just a tiny bit better about the fact that their pets have cancer. Knowing that there’s nothing they did wrong and that cancer can be reasonably described as a natural breakdown process (albeit often untimely) can be helpful for some pet owners.

Which brings me to the heart of your question: Are cancers truly occurring more frequently in pets?

No, it’s not your imagination. Pets do get more cancer these days. But here’s the thing: Modern veterinary medicine, improved nutrition and healthier pet lifestyles are contributing to increased pet longevity. Sure, cancer may be more common but pets never lived this long either.

Unfortunately, veterinarians are also seeing more cancer in many of our purebred patients, some of which are genetically predisposed to cancers. For example, flat-coated retrievers, boxers and Bernese mountain dogs are among the poster-kid breeds for early cancer deaths. Which, of course, represents a serious animal welfare issue for the veterinary profession.

But that’s the topic for another column. Let’s get back to your personal dilemma:

Sadly, thinking about cancer in rational, biological terms makes it no less than tragic whenever our pets our diagnosed with it. After all, it’s impossible to feel grateful that you’ve enjoyed so much quality time with your cat when your veterinarian’s just identified a cancerous mass inside her chest.

With the benefit of less passionate hindsight, however, perhaps it’ll help to know that you did nothing wrong. In fact, short of altering breeding practices among the genetically predisposed, there’s precious little pet owners can do to prevent cancer. For what it’s worth, though, veterinary medicine is getting way better at treating it.

Dr. Patty Khuly has a veterinary practice at Sunset Animal Clinic in South Miami. Her website is Send questions to