Petco Text Logo
Petco Pet Logo

  • Two Easy Ways to Start Earning Rewards!

My unspayed female dog has a hard breast lump. What is it?

Updated On September 23rd, 2025

Pet's info: Dog | Chihuahua | Female | unspayed | 14 lbs

My 8 year old chihuahua has a hard lump under her breast ... what could it be ?

This question includes photos that may contain sensitive content. Click to view.

View more to consider that the photos may include sensitive content.

3 Answers

Most Helpful Answer

Image profile

Answered By Amy Poole, DVM

Veterinarian

Published on July 16th, 2017

It is difficult to tell what is going on with Panthera based on the picture alone. The lump in the picture almost looks wet, so I would be concerned about a potential cyst or infected gland. Since she is unspayed, I also worry about potential mammary cancer, which we see more commonly in intact females. It can present as firm masses under the mammary glands. Dogs can also get benign masses of the mammary tissue as well. The best course of action would be to take her to your regular vet to have them evaluate her. She may need a fine needle aspirate of the lump. This is when we take a sample of cells from the area and look at it under the microscope to try to determine what the underlying cause is. It is no more painful than a vaccine and can give a lot of information as to if anything further needs to be done for Panthera or not.

Vote icon

1Pet Parents found this answer helpful

Other Answers

  • Image profile

    Answered By Robin Diers, DVM

    Veterinarian

    Published on

    Hello there. The lump on her abdomen can be anything from a benign cyst or infection to something more serious, like a mammary tumor. I recommend taking Panthera to the veterinarian to have the growth looked at. Your vet can take a sample from some of the cells in the growth to see if it should be removed.

    Vote icon

    1Pet Parents found this answer helpful

  • Image profile

    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on

    Thank you for providing pictures of Panthera's lump! I see that she isn't spayed, and unfortunately I would be very concerned this lump is a mammary tumor. They are very common in unspayed dogs, and 50% of them are malignant. Panthera needs to see a vet first thing Monday for this lump. The vet can diagnose if it is malignant or not; if it is, it will need to be removed surgically, and local lymph nodes will need to be tested to see if the cancer has spread. I know this isn't news you likely want to hear, and I'm sorry that it may be bad news for her :-(

    Vote icon

    0Pet Parents found this answer helpful

See More Answers

Related Questions

Petco Pet Education Center
Health & Wellbeing
What fish dog food helps dry skin if my dog eats Science Diet?
Is your dog's dry skin a concern? A certified vet offers expert advice on finding the best fish-based dog food alternatives to Science Diet for essential oils.
Updated on February 04, 2026
Petco Pet Education Center
Health & Wellbeing
My guinea pig has a growing lump on its neck. Can it heal itself?
Guinea pig has a growing, hard neck lump? Worried about vet costs? A certified veterinarian advises on crucial steps for diagnosis and your pet's well-being.
Updated on December 04, 2025
Petco Pet Education Center
Health & Wellbeing
My pet has a lump on their neck. What is it and what should I do?
Is your pet's lump a mystery? A licensed vet tech explains common causes like tumors or infections. Discover why a vet visit is crucial for diagnosis and treatment.
Updated on December 04, 2025
Petco Pet Education Center
Health & Wellbeing
My mouse has a growing lump. What can I do if I can't afford a vet?
Concerned about your mouse's growing lump and vet costs? A trusted Petco veterinarian provides guidance on managing her comfort during this difficult time.
Updated on December 04, 2025
Petco Pet Education Center
Health & Wellbeing
My pet has a soft lump. How long can I wait before seeing a vet?
Discovered a soft, nickel-sized lump on your pet's chest? A certified veterinarian offers expert advice on tracking changes and when to seek professional evaluation.
Updated on December 04, 2025
Petco Pet Education Center
Health & Wellbeing
Dog licking paws, fur loss, and jaw wound: Could it be allergies?
Is your Shih-Tzu crossbreed biting his feet, losing fur, or has a wound? A trusted vet explains these classic allergy signs and advises on treatments like Apoquel or medicated shampoo.
Updated on September 23, 2025
image
Have A Vet Question?

Book an appointment with the pros – our expert vets are here to help.

Book Now

Sponsored