Cancer in Pets

Many of you may be aware of, or participated in, the “Race for the Cure” as part of Breast Cancer Awareness Month. If you haven’t participated before in this awesome event, I highly encourage you to think about doing so next year- regardless of your gender.

What many people don’t realize is that dogs, cats and other pets such as rats also are prone to suffering from this disease with surprising frequency. For many years, one of the most persuasive reasons that veterinarians would advocate for spaying female dogs was to lower that dog’s lifetime risk of developing this serious medical condition. In fact, if a female dog is spayed (removal of the ovaries and uterus) before their first heat cycle (onset of puberty) their lifetime risk for developing breast cancer is reduced, compared to a dog not spayed, by 99%. If your dog has experienced one heat cycle and is then spayed their lifetime risk is decreased by 85% and after the second heat cycle the risk is decreased by 70%. After having a third heat cycle, performing the spay surgery no longer has any protective effect against the development of breast cancer.

Performing the spay procedure on cats is also protective against the future development of breast cancer and having it done before going into heat likely provides the greatest amount of protection but the exact percentage reduction in risk is not as precisely known as it is in dogs. Rats are very similar to cats regarding the effects of early spaying. The most typical early sign of breast cancer is the detection of a variably sized, quite firm, nodule(s) in that pet’s mammary tissue. The location of this tissue will vary depending on the species and breed of your pet as well as their body condition. Oftentimes, an owner is unaware of the presence of this nodule until it is detected by their veterinarian during an annual checkup. Usually surgery to remove the affected breast tissue is employed to attempt to cure your pet and can definitely be successful if caught early, just like with any number of types of cancer.

During an examination and consultation with your veterinarian you can discuss all the pros and cons of when to have your pet spayed, as well as what to do if a nodule is detected in your pet’s breast. This will help guide you in making informed decisions about how to best utilize the capabilities of your veterinarian in safeguarding the best quality of life and health for your pet. So, if next year around this time you happen to find yourself shuffling or gliding along at the “Race for the Cure,” besides thinking of all the people in your life that have been affected by breast cancer, perhaps you can devote a little time pondering what you can do to prevent or treat breast cancer in your pet.

-Dr. Ed Cohen