As a veterinary practitioner, I have seen a steady rise in the incidence of cancer in dogs and cats over my years of practice. Thus, it has never been more important to raise awareness about the rising trend of cancer in pets, and what better time to do it than National Pet Cancer Awareness Month. This article will focus on the causes for the increased incidence of cancer in pets, cancer prevention, and early detection to maximize our opportunity successful cancer treatment.
Cancer on the Rise in Pets
If I had to pick the single biggest reason for the increase in incidence of cancer in pets, it is genetics. When dogs and cats are selectively bred to favor certain physical and/or behavioral characteristics, unwanted recessive genes commonly express. If these recessive genes happen to be oncogenes, this can predispose to cancer, as oncogenes are recessive genes that can trigger transformation of normal cells into abnormal cancer cells under certain environmental conditions. This situation is made worse by unethical and/or ignorant breeders that knowingly or even purposefully breed genetically related animals.
The increased use of pesticides and chemicals to beautify lawns and maximize home garden yields, puts our pets in contact with substances known to predispose to cancer, called carcinogens. Since our pets frequently sniff and taste their environment, they are far more intimately in contact with plant life coated with cancer causing chemicals than we are.
Unchecked pollution and gas powered automobile traffic from ever increasing urban sprawl is bad for people when it comes to cancer, but even worse for our pets. Exhaust and other airborne carcinogens associated with urban sprawl pollution gets more concentrated in the air close to the ground due to gravity. Thus, our furry friends that live closest to the ground inhale a higher concentration of pollutants that we do. This is also why second hand smoke in homes is many times worse for pets low to the ground than it is for people.
Obesity is epidemic among dogs and cats and is another predisposing factor for development of cancer. Overweight and obesity can cause changes in the body that help lead to cancer. These changes can include long-lasting inflammation and higher than normal levels of insulin, insulin-like growth factor, and stress hormones. The risk of cancer increases with the more excess weight a pet gains and the longer a pet is overweight
My last reason why cancer is on the rise in dogs specifically is too many dog owners increasingly following their breeder’s advice over their veterinarian’s and letting letting their female dogs have multiple estrus (aka, heat) cycles prior to spay, or even not spaying the dog at all Among the many benefits to the spay procedure is prevention from mammary cancer, the most common cancer in female dogs. When spayed at 6 months, an age that in the majority of females predates the first estrus cycle, the risk of mammary cancer drops by 88%. If the dog is allow to have a first estrus cycle, the cancer prevention aspect of the spay drops to 55%. Spay cancer prevention after a second estrus cycle drops to 27%…and so on. If the female dog is never spayed, she will have a 21% chance of developing mammary cancer in her lifetime.
Preventing Cancer in Pets
First, a quick spoiler alert: feeding grain free does not prevent cancer in dogs and cats. Now that I got that out of the way, next, ignore your breeder and get your female dog spayed at 6 months of age. By doing so so, you will virtually guarantee that your dog will not develop mammary cancer.
Avoid pesticides and chemicals on lawns and home gardens. If the lawn and giant veggies are that big of a priority for you, spend a little extra money on a pest control company that specializes in environmentally safe organic pest control.
If you smoke, do it outside, never in the home.
If your pet is overweight, coordinate with your veterinarian to implement a safe and effective weight loss program.
Early Cancer Screening/Detection
Despite our best efforts to prevent cancer in pets, we may still lose that battle, especially with it comes to genetically triggered cancers. The key to successfully treating cancer is detecting it early. At a minimum, pets should have a through examination by a licensed veterinarian once a year, and routine wellness blood work starting at 8 years for small/medium sized dogs, 6 years for large/giant breed dogs. A comprehensive senior wellness program should also include yearly chest and abdominal x-rays and abdominal ultrasound. Using these modalities to find the cancer before the pet is even showing signs of illness will go a long way toward optimally managing or even eradicating the cancer.
