Can Dogs Get Breast Cancer?

It is not unusual for humans to be afflicted by cancerous growths within the body, with many different types of the disease manifesting within the population due to factors both genetic and environmental. One of the most common types of cancers faced by humans is breast cancer, which grows (contrary to popular belief) not just in the fatty tissues around the areolas and nipples, but potentially within a wide area of the upper frontal torso. While women are the predominant sufferers of the disease, it is also not uncommon for males to also notice the development of breast cancer tumors in their bodies.

Can Dogs Get Breast Cancer?

Yes, as with virtually all types of cancer, the disease is not just confined to humans, but can be found in most complex multicellular life forms, including dogs. That said, some breeds may find themselves more predisposed to the disease than others, meaning that owners of certain dogs may have to be more vigilant than others.

Does My Dog Have Breast Cancer?

With all the conflicting and oftentimes hyperbolic advice regarding cancer diagnosis floating around on the internet, it can be tough to know when you should start to be concerned about your dog’s health. Generally speaking however, there are a few tell-tale symptoms that, when observed together, should prompt you to seek further assistance from a veterinary professional.

The first and most obvious of these is noticeable swelling on your dog’s chest as well as a tough lump that can be felt under the skin. This can often be accompanied by changes in your dog’s behavior and moods, as well as a continued reduction in energy levels and playfulness.

The disease is most often caused by genetic problems, making it hard to predict in advance, though pronounced exposure to carcinogenic substances can often result in the development of tumors. Additionally, hormonal imbalances in your pooch can result in the mammary glands developing cancerous growths, so continued behavioral changes outside of normal mating periods can be a cause for concern (as can previous damage to the animal’s endocrine system).

Once you have identified a problem, a vet will be able to run further tests to determine the type of growth that your dog has. This will often be done by analyzing blood samples for traces of cancer cells, as well as scans of your furry companion’s body and inspection of tissue extracted from the growth itself. After this has been done, the vet will be able to recommend the best course of treatment. For more information, be sure to check out our condition guide: Mammary Gland Tumors in Dogs.

How Do I Treat My Dog’s Breast Cancer?

Once they have made a positive diagnosis of breast cancer, the vet will present you with several possible treatment options that they think will have the best chance of halting the spread of the disease and allowing your dog to return to normal life. If the disease has been caught in its earlier stages, the vet may advise the use of radiotherapy to destroy the tumor. This uses concentrated beams of radiation fired from multiple points outside the body, which then converge within the tumor, killing the cancer cells. This is fairly non-invasive and has the advantage of having an extremely short recovery time. 

However, if the disease has progressed to a more advanced stage, the vet will most likely ask for your permission to surgically remove the tumor. Due to breast cancer’s relatively shallow position within the body, the excision procedure will not usually take very long to complete. However, it will be necessary for you to provide a thorough level of aftercare for your dog in order to allow them to recover properly; giving them painkillers and antibiotics as needed and monitoring their condition for any possible complications.

For more information regarding the treatment of breast cancer in dogs, please refer to our condition guide, where you can find firsthand accounts from other dog owners.

How Is Breast Cancer Similar in Dogs, Humans and Other Animals?

Humans and other animals can contract and develop breast cancer in many of the same ways that dogs do, and can often use similar treatment methods.

• In almost all species with the condition, the cause can sometimes be impossible to determine, with no single factor providing an answer for the disease’s origin.

• Many animals with breast cancer will also have a hormonal problem that precipitates and possibly contributes to the disease. This means that behavioral changes can be one of the first clues that something is wrong.

• In cats and other small mammals, the preferred treatment method is also to surgically remove the tumor. This is because much like dogs, their small size can mean the disease can quickly spread through the body if it is not dealt with promptly.

• The rate of growth and progression of breast cancer tumors in humans and dogs are extremely similar. So much so, that dogs have been used to test new drugs intended for use on humans.

How Is Breast Cancer Different in Dogs Different, Humans and Other Animals?

While the disease can bear similar hallmarks across cases found in many species, there are significant variations in how the condition is diagnosed and treated.

• Firstly, humans will be able to relay verbal information to their doctors, meaning that isolating an environmental cause of the problem may be much easier, preventing a recurrence of the issue in the future.

• While the preferred method for dealing with breast cancer in most animals is excision, humans will typically opt for a combination of chemotherapy and radiotherapy. This is partly for cosmetic reasons and partly because of the fact that the long lifespan of humans means that there is more opportunity for the cancer to reappear. By adding a course of chemotherapy to the treatment, a doctor can hopefully kill all of the cancerous cells in the body.

• The cost of treating breast cancer in a cat is considerably less expensive than the cost of treating the same condition in a dog. This is mainly due to the fact that smaller animals will on average require less in the way of pharmaceuticals.

Case Study

A notable example case that demonstrates the often inscrutable nature of breast cancer is that of a thirteen-year-old Cocker Spaniel in Korea. The animal presented with both a mass in his breast tissue and a tumor growing on one of his testes. The growths were surgically removed as per surgical procedure, but no hormonal abnormalities were detected. This was unexpected, as it is commonly hypothesized that occurrence of the condition in males is due to particularly high concentrations of estrogen in the body. This means that there are perhaps more significant factors at work in many cases of the disease than were first thought.