Mammary Tumors in Cats: Signs, Risks, and When to See Your Vet

Hearing that your pet may have cancer is a terrible shock. If you are noticing signs that your cat is sick and you suspect a mammary issue, that can be a very scary time. We understand that you are anxious and have many questions.

As pet parents and natural-care specialists at Zumalka, we want to help you understand feline mammary tumors and breast cancer so you can have informed conversations with your veterinarian.

In this article, we will look at the causes and risk factors of mammary cancer in cats, and how mammary tumors differ from breast cancer. We will also go over the symptoms to take note of when it comes to malignant mammary tumors.

Finally, we will cover life expectancy and the care options veterinarians commonly discuss for this condition. Mammary gland tumors or breast tumors, even when they are not malignant, should not be ignored, because they can possibly progress into cancer over time.

If you need to know anything else about cancers affecting cats, please refer to our complete guide to cat cancer for more details.

What is Breast (Mammary) Cancer in Cats?

Tumors can develop in the mammary glands (breast tissue or the mammary chain) on the belly. Cats have four mammary glands (with nipples running parallel) on each side of their belly. A mammary tumor affecting the breast tissue can develop in any one of these glands and is referred to as a "primary tumor."

It is crucial to take note that the more pronounced the affected mammary gland is, the farther the tumor cells have spread and developed in the mammary tissue, particularly in the epithelial tissue regions.

Either a particular segment of the mammary chain will be affected or the entire chain itself. It is also possible that mammary tumors in cats will have a more significant effect on a particular mammary gland or glands compared to the others.

Additionally, a malignant mammary gland tumor can potentially transform into mammary carcinoma or breast cancer about half the time. This is the biggest reason why there is a much higher possibility of survival if this serious health issue is caught early by a veterinary oncologist.

What's really alarming is that once malignant mammary tumors spread to the regional lymph nodes, it won't be long until they will affect other parts of a cat's body like the internal organs, bones, and brain.

A male cat can be prone to mammary tumors and breast cancer, too.

Breast cancer is the third most common cancer affecting cats. The majority of these tumors are malignant, meaning they are cancerous and can spread to other areas of the body. Interestingly, male cats can also develop mammary tumors.

However, female cats are more likely to develop this cancer than male cats. One of the best ways to reduce your feline companion's risk of developing mammary tumors is an early spay at a young age, or just before her first heat cycle.

Spaying your kitty before she is 6 months old significantly reduces the risk of mammary tumors in cats by approximately 91%.

Moreover, apart from helping reduce your feline best friend's susceptibility to tumor development in the mammary gland or glands, early spaying prior to her first heat cycle also curbs the possibility of the uterine infection called pyometra, which involves female reproductive hormones.

Older cats over the age of 10 are also at a higher risk of developing this cancer. Some breeds, such as Siamese cats, also seem to be diagnosed with mammary cancer more often and at a younger age than other breeds.

Are Mammary Tumors the Same as Breast Cancer in Cats?

While the terms mammary gland "tumors" and "cancer" are quite similar, they are actually distinct from each other. Both involve the abnormal reproduction of mammary gland cells, but each requires a different diagnosis, management, veterinary care plan, aftercare, and even surgical removal in some cases.

The mammary glands are targeted

When mammary gland tumors are concerned, there is always a particular mammary mass that develops. Although larger tumors can be easily discerned, tumors smaller in size need further testing to be diagnosed properly.

This can be done through a comprehensive physical as well as the collection of tissue samples, chest x-rays, fine needle aspiration (FNA), chest radiographs, abdominal ultrasound, and a complete blood count, among other techniques practiced in veterinary medicine.

A combination of these techniques may be conducted to really arrive at an accurate diagnosis.

Moreover, tumor size is considered an important prognostic factor since it can somehow help assess the level of a cat's risk when mammary gland tumors are present. The size of tumors in cats is also used as a factor in determining median survival time in some cases.

The lymph nodes can also be possibly compromised

When mammary tumors in cats are concerned, there is a big possibility that the lymph node will be affected. A common tumor usually spreads to the groin (inguinal area) or axillary region (located in the areas below the shoulder).

When veterinarians discuss radiation therapy or chemotherapy in cats, part of that plan is often aimed at these affected lymph nodes.

Mammary Cancer in Cats: Symptoms

It’s important that you examine your cat often to look for the signs of a mammary tumor.

A careful examination of your cat's belly will do the trick. Make sure you don't do this when your kitty has an upset stomach since he won't be that cooperative!

Most cats will exhibit nipples that are swollen, or you may feel a small, firm lump under the skin near the nipple. As we've stressed previously, the tumor can spread to the other mammary glands and nearby lymph nodes.

Hormones play a key role in growth and development when it comes to mammary tumors or breast cancer. Excessive production of hormones can make a tumor become quite big.

Location of cat lymph nodes

Here is a quick guide on the lymph node locations on your cat's body:

• Below the jaw

• Front of the shoulders

• Beneath the shoulders

• The groin area

Mammary gland tumors in cats can be prone to infection and sores

In advanced cases, the tumor might become an open sore and could even become infected. It can get worse if veterinary care is delayed.

As we've emphasized earlier, make sure to check your cat regularly so you can notice any unusual lumps as early as possible. A careful physical exam at home can help you spot changes to show your veterinarian.

Is mammary cancer painful in cats? When it is in the beginning stages, your cat won’t be in any pain. As the tumors grow and spread, your cat might feel sick and uncomfortable, especially if the tumors open up and get infected.

Other clinical signs you should look out for

Other signs you need to keep an eye on include:

• Sores in and around the breast area of cats that never seem to go away

• Discharge from the tumor

• Abnormal puffiness of the nipple and breast tissue

Cat Mammary Cancer: Life Expectancy

The earlier mammary cancer is found and addressed with veterinary care, the better the outcome for your cat.

If the tumor is small and hasn’t spread, cats can live for 4 years or longer after diagnosis. For large or more advanced tumors, survival time may only be a few months.

In most cases, your vet might recommend surgery such as radical mastectomy in cats to remove the tumors and affected mammary glands. They may also discuss chemotherapy after surgery.

Chemotherapy can have adverse side effects you should know about: nausea, diarrhea, significant loss of appetite, coat dullness, and weakness. Other rare, but still possible, side effects can include cardiovascular damage and kidney failure. Your veterinarian can explain what to expect for your cat.

Natural immune support alongside veterinary care

Many pet parents also look for natural options that can sit alongside conventional veterinary care. If you are looking for a natural product for daily wellness support, you can learn more about PiptoPet.

PiptoPet is a birch-polypore formula (Fomitopsis betulina) designed to support a healthy immune response in cats and dogs. It is meant to complement your veterinarian's care plan, not replace diagnosis, surgery, chemotherapy, or other veterinary treatment. Talk with your veterinarian before adding anything new to your cat's routine.

About the author

Suzie Cyrenne

HOMEOPATH & CO-FOUNDER OF ZUMALKA

Suzie Cyrenne has dedicated more than 20 years of her life in making and improving natural animal health solutions in the global setting.

Being the co-founder of Zumalka, Suzie is a forerunner in enhancing the lives of pets through natural and homeopathic options using the knowledge she has gained from the Classical Homeopathy School in Quebec.

Through the guidance of her mother-in-law and fellow natural health expert, Denyse Lessard, Suzie constantly devotes herself to create premium pet products that are aimed at dealing with the root causes of wellness problems and not just their symptoms.

Besides immersing herself in books, personal development and visiting new places, Suzie also enjoys keeping herself in tiptop shape by snowboarding and taking daily hikes with her husband and Zumalka co-founder, Matt Lessard, and their Golden-Doodle, Westin.

Find out more about Suzie when you click HERE.