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My dog has a painful lump on her stomach near a nipple. What is it?

Updated on September 23rd, 2025

Pet's info: Dog | Mixed Breed Small (up to 22lb) | Female | unspayed

Hello! My dog has a ball on her stomach where one of her nipple is. It hurts her if we touch it. I was wondering what the possibilities were.

4 Answers

Most Helpful Answer

Answered By Sarah Derksen, DVM

Veterinarian

Published on October 30th, 2017

Hi. This is a very big mass. If it is firm and painful, this is concerning in an unspayed, older pet is cancer unfortunately. Besides a cancer, other possibilities include infection, cyst, lipoma, a benign mammary tumor, hernia, etc. She should be fully checked out and have the mass sampled to get an answer. The sooner the better in this case.

4Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Lindsey Edwards MVB, BSc, IVCA
Veterinarian
Published on May 15th, 2019
These sound like mammary tumours (similar to breast cancers). Please have her assessed urgently as surgical removal may be recommended as soon as possible as long as there is no evidence they have spread internally
1Pet Parents found this answer helpful
Answered By Lindsey Edwards MVB, BSc, IVCA
Veterinarian
Published on May 18th, 2019
It is impossible to say for sure but approximately 50% of mammary (breast) lumps are cancerous and they are particularly concerning in older and entire (non-neutered) females add if there is any discoloration (appears bruised in picture), pain or discharge. I strongly recommend an urgent vet check given the red flags which are present
1Pet Parents found this answer helpful
Answered By Dr. Melanie, BVSc MS
Veterinarian
Published on February 4th, 2020
Unfortunately cancer is a possibility. I see that Viski isn't spayed, and dogs who aren't spayed have a 25% chance of developing mammary tumors. If they do develop mammary tumors, 50% of them are malignant.
1Pet Parents found this answer helpful

Smart Picks for Smart Questions

Related Questions

My unspayed female dog has a firm bump on her stomach. What is it?

It looks like the bump is inline with her mammary chain. Intact females are prone to developing mammary tumors. Is is about a 50% chance of it being malignant. I would recommend surgical removal with biopsy. I usually recommend that the patient also be spayed at the same time to decrease the likelihood of further mammary tumor development. Best of luck and thank you for using Pet Coach.

Updated on September 23rd, 2025

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My dog has a lump on her stomach, is it serious and what should I do?

This lump/growth should be ideally examined by your veterinarian to have a definitive diagnosis. Your vet will examine it and possibly perform with an FNA (fine needle aspiration) or a biopsy. Differentials would include skin cyst, infections or benign or malignant type of tumors. Hope this answer was helpful, but please do not hesitate to contact us again on the forum or by requesting a consultation if you have any more questions or to discuss it any further. If this answer was helpful please let us know, this will be used to improve our service!

Updated on September 23rd, 2025

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My unspayed dog has a soft, painless stomach lump. Is it an emergency?

Thank you for submitting your question regarding Giselle. If she is eating, drinking and acting normal, then it is likely not an emergency. However, she should have it evaluated by her veterinarian. She may have developed a mammary mass. This is more common in dogs that have not been spayed. Her veterinarian will perform an examination and then possibly collect a sample from the swelling to analyze. I hope this information helps!

Updated on September 23rd, 2025

My dog has stomach bumps that don't bother her. What are they?

Thanks for using Petco Pet Education Center, formerly Petcoach! This looks like a mammary tumor. This could be a benign or malignant growth. This is often differentiated by a test called a fine needle aspirate (FNA) which is a pain free, inexpensive and easy procedure which in most cases will help reach a diagnosis. Sometimes a biopsy is needed for a definitive diagnosis. I recommend that you have her evaluated by your veterinarian for further assessment and treatment. I am really hoping for something benign. Good luck and have a good day!

Updated on September 23rd, 2025

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My unspayed dog has hard blue lumps near her nipple. Is it serious?

She may have mammary cancer which is fairly common in unspayed dogs. Your vet can perform either a biopsy or a fine needle aspirate and cytology to confirm the nature of the mass. If it comes back as mammary cancer, full screening pre-operative bloodwork as well as chest radiographs to rule out metastasis to the lungs will likely be discussed. If chest rads show that cancer has already spread to her lungs, unfortunately surgical removal under anesthesia may not be practical. Good luck-

Updated on September 23rd, 2025

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My 1-year-old female dog has lumps under her nipples. What is it?

Hello. This is probably benign mammary hyperplasia, but you do want to have this looked at, especially if she has been spayed. If she has not been spayed & has never been with a male dog, then this could be related to a false pregnancy. Also, has she been in contact with anyone who is on hormone replacement therapy? Sometimes, this can rub off on a pet & cause mammary enlargement. If no outside cause can be found, then have her spayed if that has not already been done, & submit a biopsy to see exactly what is going on with the tissue. Thanks for using Petco Pet Education Center, formerly Petcoach.

Updated on September 23rd, 2025

Why is my dog's swollen stomach lump making her unable to walk?

I am very sorry to hear about your dog. What you are describing sounds like most likely a tumor. There are many different types of tumors. Two of the more common we see in this area are lipomas, which are fatty tumors and feel soft/squishy, and sarcomas which are firmer feeling. Unfortunately it sounds like this is large and causing her problems. She needs a visit to the vet's office to examine the tumor and see if it can be surgically removed. They may want to take an x-ray and may want to do what is called a "fine needle aspirate" to collect cells to try to identify the type of tumor before surgery.

Updated on September 23rd, 2025

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