Mammary Gland Tumors in Dogs: Causes, Treatment, and Prevention

Quick Summary

• According to experts, mammary gland tumors in dogs are common but only half of the cases are malignant.
• Intact dogs are more likely to get mammary tumors. Studies show that female dogs spayed before the first heat cycle have the least chance of getting tumors in their mammary glands.
• Depending on the severity of the tumor, treatments for mammary tumors range from surgical removal, chemotherapy, or radical mastectomy.

Most people are aware that breast cancer is a serious disease among women. Some may not be aware that it can happen in female dogs as well. I have found that mammary gland tumors are the most common types of tumors that develop in female dogs. In fact, among unspayed females the risk is 26 percent—this is three times the risk of breast tumors in women.

Do you think your dog has mammary tumor? Read my guide.

Mammary Gland Tumors in Dogs: Malignant and Benign Tumors

Tumors in the mammary tissue have about equal chances of being either malignant or benign, with multiple tumors being more common. There have been studies showing that several sporting breeds, including Poodles, Boston Terriers and Dachshunds, are more likely to develop a mammary tumor. The good news is that since it rarely occurs in female dogs that were spayed before their first heat (it rarely occurs in makes dogs too), a mammary tumor is one of the most preventable types of cancer in dogs.

Benign mammary tumors are those that do not spread to other parts of the body, while malignant mammary tumor does. In some cases a dog may have both benign and malignant tumors.

What Are The Symptoms of Mammary Gland Tumors?

The most common sign of a mammary gland tumor in your dog is visible lumps in that area. These are some additional symptoms, according to VCA Animal Hospitals:

• Secretion of clear, milky or blood-stained fluid from the teat
• Ulceration
• Inflammation and/or secondary infection
• Loss of weight, body fat and muscle
• Weakened immune system
• Shortness of breath

How are Mammary Gland Tumors Diagnosed?

If you notice a mass or lump on your dog’s mammary glands, then immediately take her to your vet. Your vet will perform a chest X-ray to determine whether your dog also has lung metastases (tumors that spread to the lungs) before starting any treatments. Typically the vet would also perform an ultrasonography to determine other underlying health issues affected ares such as the pelvic lymph nodes.

A biopsy of your dog’s mammary gland tumor will then be needed to see whether it is benign or malignant. Note that early detection is essential for successful treatment. If you notice any changes in your dog’s mammary glands, I highly suggest to contact your veterinarian right away.

What Are The Treatments for Mammary Gland Tumors in Dogs?

The main treatment for mammary gland tumors is surgical removal of the cancerous tissue. Depending on the severity of the mammary cancer and size of the tumor, it may be just a lump or a whole gland and surrounding lymph node that is removed. In cases of inflammatory mammary carcinoma, surgery is not recommended. Instead, the dog may need radiation therapy and chemotherapy. In cases of multiple tumors, a veterinarian may need to perform a radical mastectomy. In this procedure, multiple glands and some of the associated regional lymph nodes will be removed.

While spaying at an early age can decrease the risk of mammary gland tumors, spaying at the time of tumor doesn’t adversely affect the dog’s condition. Additional treatment may be needed. It’s depending on how severely the tumors have progressed. Some dogs may need to undergo therapy, through chemotherapy. Chemotherapy is not successful with mammary gland cancer.

Additional Canine Mammary Tumors Prevention

Today there are new expert researches that focus on using certain enzymes to destroy tissue and act as inhibitors of new tumor blood vessel formation. This is also related to gene therapy. Additionally, you can give your dog a supplement containing reishi mushroom, which has the capability to boost your dog’s immune function, act as an anti-inflammatory and most importantly, fight canine cancer.

FAQs

How long do dogs live with mammary tumors?

Dogs with malignant mammary tumors often only live up to less than one year. Mammary sarcomas and inflammatory mammary carcinoma are even more serious, leaving dogs with only a few weeks or months to live.

What are the first signs of mammary cancer in dogs?

The first signs that a dog has mammary cancer are bloody discharge or pus coming out of the nipples, painful and swollen breasts with multiple bumps, loss of weight, body fat and muscle.

How do you treat mammary gland tumors in dogs?

Tumor removal through surgery is often the treatment for mammary gland tumors in canines.

What does a mammary gland tumor look like in a dog?

A dog with mammary gland tumor will most likely have either a hard or soft lump in her breast area. In severe cases, this lump would burst and leak pus out.