pink breast cancer awareness ribbonAre you aware that dogs and cats can get breast cancer just like people?

While many are surprised to learn that mammary cancer affects our pets, it’s actually a very common problem. In fact, breast cancer is more commonly found in pets than in people. Statistically, one in four intact (not spayed) female dogs will develop a mammary tumor, and it is the third most common cancer for cats.

Approximately 50% of mammary tumors in dogs and about 90% of mammary tumors in cats fall into the malignant category. Malignant tumors are what we think of as the “bad” kind of tumor. Malignant tumors are invasive and may spread to other organs, and are usually very aggressive.

No pet owner wants their beloved pet to experience this disease. Learn what you need to know about breast cancer and your pet so that you can help your pet stay healthy.

Which Pets Are At Risk?

There are a handful of characteristics that have been shown to put certain pets at a higher risk of developing a malignant breast tumor. Owners of pets with these risk factors should pay very close attention to any changes in their pet’s mammary chains and be sure to have their pet examined by a veterinarian on a routine basis.

  • Being a non-spayed female greatly increases the risk.
  • Pets that have been spayed later in life are also at an increased risk.
  • Siamese cats are more likely than other cats to develop breast tumors, and often do so at a younger age (9 years on average vs. 14 years in other breeds).
  • Pets that have been exposed to a progestin hormone are at increased risk. These are not typically used in veterinary medicine any longer.

Can I Protect My Pet?

The most effective way to prevent mammary cancer is to spay your pet.

Female dogs who were spayed before their first heat cycle have been shown to have virtually zero risk of developing breast cancer. However, dogs that have had one heat cycle have a 7% risk, and the risk goes up to 25% for those who have had more than one heat cycle.

Even if your pet is in a high risk group, it does not mean that it is too late to spay them. Mammary tumors are driven by female hormones, and spaying at any age is helpful.

What Happens if My Pet Does Develop Mammary Tumors?

Thankfully, not all tumors are malignant. If you notice an abnormal growth in your pet’s mammary region, it is important to have it checked out right away. Time can be essential when it comes to successful treatment, and this is a case where acting early can make a big difference in outcome.

If and when a mammary tumor is found, your veterinarian will first want to determine what type of tumor is present and whether it is malignant. By surgically taking a biopsy of the tumor, your vet will be able to tell if the tumor is malignant or benign, and determine what course of treatment might work for your pet. Depending on these results, further surgery, radiation therapy, chemotherapy, and/or anti-estrogen therapy may be recommended.

Mammary cancer is a serious diagnosis and, whenever possible, it is best to prevent it from occurring at all. Don’t delay spaying your pets. If you have questions about having your pet spayed, or if you think your pet might have a mammary tumor, please do not hesitate to call.

We are happy to help in any way possible.