Mammary Gland Enlargement in Cats
Written By hannah hollinger
Published: 10/08/2016Updated: 05/14/2021
Veterinary reviewed by Michele K.
Mammary Gland Enlargement in Cats - Signs, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Mammary Gland Enlargement?
While female cats are far more susceptible to these problems, nipple and mammary gland swelling is sometimes seen in male cats as well. A female who is intact is more at risk than a female that is spayed. If unusual mammary gland swelling is noticed while a cat is nursing kittens, veterinary attention may be needed for the kittens along with the mother as the infection can easily spread between the two. 
Nipple and mammary swelling are the outside manifestations of mammary gland enlargement. Most cats have eight nipples, and in the case of enlargement or inflammation, one or more nipples may be affected. Normal events in a female cat’s life can lead to the swelling of mammary tissue, such as pregnancy and lactation. However, many infections and other conditions which can be life-threatening also create mammary gland enlargement. 
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Mammary Gland Enlargement Average Cost
From 433 quotes ranging from $200 - $1,400
Average Cost
$600
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Symptoms of Mammary Gland Enlargement in Cats
Generally, when the condition is abnormal and needs treatment, multiple signs may arise. 
  • Swelling of the nipples or mammary tissue
  • Painful nipples
  • Redness
  • Discharge from nipples
  • Ulceration of the nipples and breast
  • Loss of appetite
  • Fever
  • Enlarged lymph nodes
  • Edema of the skin on hind legs
  • Refusal to nurse (if female with kittens)
  • Sick kittens (if nursing)
Causes of Mammary Gland Enlargement in Cats
Besides the normal cause of pregnancy, enlarged mammary glands can be the sign of a bigger internal issue in the cat. A veterinarian is best at determining the exact cause of the swelling, which will lead to a faster diagnosis and treatment for the cat. Causes include:
  • Pregnancy
  • Mastitis (mammary gland infection while lactating)
  • Galactostasis (milk collection in mammary gland while weaning)
  • Feline Mammary Hypertrophy (benign masses)
  • Mammary cancer
  • Mammary Hyperplasia (from high levels of progesterone)
Diagnosis of Mammary Gland Enlargement in Cats
A veterinarian will need the cat’s full medical history upon arrival at the clinic. A physical exam will be performed in which the nipples and mammary tissue will be closely examined for signss that match with mammary gland conditions. Some issues may not be serious and might resolve on their own, while other conditions can be life-threatening.
A range of diagnostic testing might be done, generally starting with blood work. This may include a complete blood count and a biochemical profile. A biopsy of the enlarged tissue may be taken for further microscopic evaluation (a histopathological examination). Chest and abdominal X-rays may be needed to check for tumor location and pinpoint any metastasizing (spreading). Urinalysis can be used to confirm and identify any bacteria present in the cat. 
Treatment of Mammary Gland Enlargement in Cats
There are a variety of treatments available, depending on the condition present. If the cat is dealing with an infection (as in the cases of mastitis), this can be a medical emergency. Immediate attention is needed to stabilize the cat enough to receive treatment.
Mastitis 
Treatment for mastitis includes an antibiotic prescription to clear up any infection and painkillers to help the cat endure the pain associated with this condition. Your veterinarian may also recommend that you apply a warm compress periodically to help with drainage. 
Mammary Cancer 
This type of cancer is very aggressive and often spreads. It usually occurs in multiple nipples at once. The surgical removal of affected glands (mastectomy) is recommended, especially if the cancer is in its early stages. If the cat is not a good surgical candidate, chemotherapy may be the only treatment option. 
Feline Mammary Hypertrophy 
Advised treatment for this condition is a full spay (ovariohysterectomy). While these surgeries are more routine, if the cat is suffering from poor overall health, the procedure can be very taxing. 
Mammary Hyperplasia
To alleviate this issue, removal of the source of progesterone is needed. This generally leads to an ovariohysterectomy. If ulceration of the glands has occurred, glands may be removed if the cat is stable enough. Painkillers will be prescribed to help the cat get through the days after the surgery. 
Pregnancy or Galactostasis 
Both of these causes of mammary gland enlargement will resolve on their own with time. 
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Recovery of Mammary Gland Enlargement in Cats
If the underlying condition is mammary cancer, overall prognosis is guarded. This cancer has a high tendency to spread throughout the body, most commonly to the lymph nodes, liver, kidneys, lungs and adrenal glands. If the cancer is caught early and the tumor found is less than 2cm in diameter, surgical removal offers a much higher survival rate than in more advanced cases.
If the cat has received a mastectomy or an ovariohysterectomy, signs of infection need to be watched for. Abide by all recommended at-home care from your vet. A post-surgical clinic visit is often required to allow the veterinarian to check that the healing process is happening successfully. With many of these conditions, spontaneous remissions can occur. 
Mammary Gland Enlargement Average Cost
From 433 quotes ranging from $200 - $1,400
Average Cost
$600
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Mammary Gland Enlargement Questions and Advice from Veterinary Professionals
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Tabby
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Six Years
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2 found this helpful

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2 found this helpful

My pet has the following symptoms:
Swelling
My adult cat has a swollen purple nipple
Aug. 7, 2020
Answered by Dr. Michele K. DVM
2 Recommendations
Thank you for your question. It is difficult to tell from the picture, but it looks like there may be an infection or a tumor there. It would be a good idea to have your cat seen by a veterinarian, as they can examine the area more closely and see what might be going on. Once they know more, they will be able to give you advice on treatment. I hope that all goes well for your cat.
Aug. 8, 2020
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Domestic cat
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Fourteen Months
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0 found this helpful

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My pet has the following symptoms:
Large Lump On Abdomen
Hello My momma cat just finished weening her babies and they have been rehomed for over a week now. They were 9 weeks old. I noticed today that she has a large lump on her abdomen. It’s very concerning.
Aug. 6, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. Unfortunately, without being able to see her or examine her, I don't know if the lump is a problem or not, but a lump the size of a baseball would concern me, as well. It is good that you are taking her to be seen tomorrow, as they will be able to examine her and give you more information as to what the lump might be. I hope that all goes well for her!
Aug. 6, 2020
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Tuxedo cat
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9 months
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3 found this helpful

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3 found this helpful

My pet has the following symptoms:
Swollen Nipple
My nine month old male cat has one swollen nipple that looks infected and might have puss in it? It’s larger then all his other ones and infected. Please help I’m worried and not sure what this could be, he has a vet visit Saturday!
Aug. 4, 2020
Answered by Dr. Michele K. DVM
3 Recommendations
Thank you for your question. It does look like there is a discharge that looks infected, and it would probably be best to have him seen by a veterinarian. If he is doing okay otherwise, eating and drinking and generally acting like himself, you should be okay to wait until Saturday. If he becomes lethargic, is vomiting, or the area is getting worse, then I would try to get his appointment sooner. I hope that all goes well for him.
Aug. 4, 2020
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Mutt
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Seven Years
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Red, Leaky Nipple
My male cat has a red nipple and I think it is leaking because the area is sticky. I noticed that it looked sticky last week and I tried to clean it but the next day it was back and it was even more red.
July 30, 2020
Answered by Dr. Michele K. DVM
0 Recommendations
Thank you for your question. If your cat is a male, it is uncommon for them to develop mammary cancers, but not impossible. He may have an infection or some kind of irritation that needs treatment, or a parasite. Since this has been going on for a week, and doesn't seem to be getting better, it would be best at this point to have him seen by a veterinarian. They would be able to look at the area, see what might be going on, and give you an idea as to what treatment might be needed. I hope that he is okay!
July 30, 2020
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American shorthair
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One Year
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1 found this helpful

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1 found this helpful

My pet has the following symptoms:
Swollen Nipple And Red
My cat is nursing, she has one swollen nipple it does not seem to hurt her when I touch it. She does fuss when the kittens nurse. There is hair pulled out and sore under her last two nipples but again when I touch the area it does not seem to hurt her. The kittens are two weeks old today.
July 25, 2020
Answered by Dr. Michele K. DVM
1 Recommendations
Thank you for your question. It is not uncommon for cats to have red or swollen nipples while nursing kittens, it can be hard on them. If she stops producing milk, or it seems very uncomfortable to her, or you see any pus or discharge from the nipple, then it would be best to have her seen by veterinarian. As long as things are seeming normal otherwise, it may resolve in a day or two. I hope that all goes well for her.
July 25, 2020
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Gray cay
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Cuddles
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12 Years
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0 found this helpful

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0 found this helpful

My pet has the following symptoms:
Swollen Nipple
One of my cat nipple is big compare to the others, her nipple is pink & she been acting normal and had it for a while, I’m not sure what it is though, I also didn’t bring her to the vet yet. What do you think it is? I am a little worried.
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moggy
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Kitty
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1 Year
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My pet has the following symptoms:
Lump With Little Blue Colour In Breast
My cat has a litter of kittens it's 5 week now and I noticed some lumps near her breast. The local vet are not much educated and could not figured out what is it. But her nipples surrounding is becoming blue. She is active and eat food normally, but meow a lot all the time. Can anybody help me.
Mammary Gland Enlargement Average Cost
From 433 quotes ranging from $200 - $1,400
Average Cost
$600
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