Mammary Cancer in Cats
Mammary Cancer in Cats - Symptoms, Causes, Diagnosis, Treatment, Recovery, Management, Cost
What is Mammary Cancer?
Mammary gland cancers in cats are similar to breast cancer in humans. Mammary cancer is usually a malignant adenocarcinoma that appears in one or more of a cat’s breasts. Other forms of breast and mammary cancer in a cat include adenomas, duct papillomas, and sarcomas. Females, as well as males, can develop this form of cancer. When it appears in cats, it can be fatal, even if treated with surgery, radiation and chemotherapy. Adenocarcinomas are one of the most aggressive types of cancer, metastasizing or moving to the lymph nodes and other parts of the cat’s body. Siamese cats, cats between the ages of ten and fourteen years of age, and intact (not spayed) females are most likely to develop mammary and breast cancer.
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Mammary Cancer Average Cost
From 228 quotes ranging from $3,000 - $8,000
Average Cost
$6,000
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Symptoms of Mammary Cancer in Cats
Cat owners and their vets will notice the following symptoms:
  • Swelling of the breasts or mammary glands
  • Infection in and around the glands and breasts
  • Skin ulceration surrounding the masses
  • Sores that don’t heal
  • Pain
  • Fever
  • Tumors appear as firm nodules firmly attached to the underlying muscle and skin
  • Clear, bloody, or milky discharge from the cat’s nipples
  • Dead (necrotic) tissue at the site of the tumor
  • Unexplained weight loss
  • Unwillingness to eat
  • Weakness
Causes of Mammary Cancer in Cats
Several factors seem to influence why cats develop mammary or breast cancer:
  • Leaving cats intact (not spayed)
  • Allowing the cat to have several heat cycles or litters before spaying
  • Cat’s age (cancer usually begins when cats are between 10 and 14 years of age)
  • Hormones: if cats receive medications with estrogen, they are more likely to develop mammary or breast cancer
  • Siamese, Persian and other Oriental breeds, as well as domestic shorthaired cats are at higher risk of developing tumors of the breasts or mammary glands at younger ages
Diagnosis of Mammary Cancer in Cats
When a pet owner brings in a cat with mammary and breast tumors, the vet will conduct a full physical exam, focusing most on the mass or masses. They will palpate the masses and nearby lymph nodes, looking for a spread of the mass. 
Once this part of the exam is done, the vet orders X-rays, which enable them to determine how big the tumors and whether it has spread. In addition, the vet may order an abdominal ultrasound, looking for a spread of the tumor to other organs. They may also carry out a fine-needle biopsy, where they aspirate lymph nodes to check for the presence of cancer cells. They will order a complete blood count and a biochemical profile, which allows them to check on the cat’s overall health. Other diagnostic tests may include urinalysis and a clotting profile of the drawn blood sample. 
If surgery is decided upon, the surgeon may take a small sample of the tumor and send it to pathology for a biopsy, especially if they are sure the cat has mammary or breast cancer. This biopsy allows the pathologist to determine exactly what kind of cancer the cat has.
Treatment of Mammary Cancer in Cats
When a pet owner brings in a cat with mammary and breast tumors, the vet will conduct a full physical exam, focusing most on the mass or masses. They will palpate the masses and nearby lymph nodes, looking for a spread of the mass. 
Once this part of the exam is done, the vet orders X-rays, which enable them to determine how big the tumors and whether it has spread. In addition, the vet may order an abdominal ultrasound, looking for a spread of the tumor to other organs. They may also carry out a fine-needle biopsy, where they aspirate lymph nodes to check for the presence of cancer cells. They will order a complete blood count and a biochemical profile, which allows them to check on the cat’s overall health. Other diagnostic tests may include urinalysis and a clotting profile of the drawn blood sample. 
If surgery is decided upon, the surgeon may take a small sample of the tumor and send it to pathology for a biopsy, especially if they are sure the cat has mammary or breast cancer. This biopsy allows the pathologist to determine exactly what kind of cancer the cat has.
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Recovery of Mammary Cancer in Cats
Generally, the prognosis for cats with breast or mammary cancer is guarded, with a few exceptions. If the cat’s tumor is smaller than 2cm, it may survive for up to three years. Cats with tumors between 2 and 3cm may survive fur up to two years and cats whose tumors are larger than 3cm may survive for up to six months. If the cat’s treatment for small tumors that were caught early is aggressive, the cat may live for between two and three years. Cats who underwent large resections (having one or both mammary chains removed) lived post-surgery for up to three years while those cats who had only the tumor removed lived for only one year after surgery.
It benefits the cat to be seen immediately by the vet when its owner detects a suspicious lump.
Over 60 percent of tumors that have been removed will redevelop within 12 months. Because cancerous mammary tumors are so aggressive in cats, their overall prognosis is guarded, especially since these tumors metastasize.
Mammary Cancer Average Cost
From 228 quotes ranging from $3,000 - $8,000
Average Cost
$6,000
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Mammary Cancer Questions and Advice from Veterinary Professionals
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Siamese mix
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Seventeen Years
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My pet has the following symptoms:
Bump Around Nipple Area
My vet has said that Tula more than likely has mammary cancer. She has a tumor on one of her nipples. She is eating, drinking, no lethargy. No change in behavior. She barely licks it. My vet states she is not a viable candidate for surgery due to her age, she has a mild heart murmur, she has hypothyroidism ( which she has been treated for the last 3 years) and her potassium is low. She gave me medication to bring the potassium up and we cut back on the Methimazole by a quarter. Should I seek another opinion or just go along with my vet until it’s “time?”
July 12, 2020
Answered by Dr. Sara O. DVM
0 Recommendations
Hello, Without examining your dog it would be hard to tell if she could have surgery or not. A second option from another vet may help you decide if your dog needs to have surgery or not. It does sound like your vet was correct with a mammary tumor. I hope your dog starts to feel better soon.
July 12, 2020
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Maine Coon
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Squee
dog-age-icon
8 Years
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24 found this helpful

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24 found this helpful

My pet has the following symptoms:
Lump
Fluid Expressed
My cat starting exhibiting symptoms in June. Intially, I felt a lump on her mammary, and made an appointment for the following week. I've predominately had male cats in the past, so it never occured to me that my cat, my sweet Squee, could get mammary cancer. I felt so guilty, like I had been neglecting her. The mass was about the size of a pinky finger tip, tubular in nature. The vet examined her, and was able to completely express the mass down, I was relieved. All her lab work came back great as well. A month later, the mass returned, hardened this time. I took her back, the vet advised surgery. I took about 6 weeks to decide. Her appetite never lacked nor her energy leading up to the surgery, thus I waited. I was hoping it was just scar tissue. It didn't seem to be growing, but I went ahead and scheduled the surgery for last week. It was a grade 1 mammary adenocarcinoma on her left upper mammary. Squee is doing well since the surgery. She also has a heart murmur, making the surgery more dangerous. They only removed the mammary and tumor, and I'm concerned that we should be more aggressive, and continue with the rest of the chain, but the longer the surgery, the more taxing on her little heart. The next step for me is going to be having her x-rayed to ensure the tumor was isolated. I hate this. I just want my sweet, little companion to be okay.
Sept. 18, 2018
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Domestic longhair
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Whiskey
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8 Years
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7 found this helpful

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7 found this helpful

My pet has the following symptoms:
Back Leg Weakness
8 year old kitty. Fixed at age 5. Had mammary lumps about a year and a half ago, benign. New lumps formed about a year later. They grew very quickly and very large. One is 10c, one is 2c. Xray shows 2 possible masses in lungs and her back legs have become extremely weak in a week's time frame. She seems happy, eats/drinks aaaaaand is alert. Vet recommend quality of life. Is it worth getting a blood test or having the lumps removed? She also lost a few lbs in 2 months.
Sept. 7, 2018
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Short hair domestic
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Nickey
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14 Years
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5 found this helpful

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5 found this helpful

My pet has the following symptoms:
Appetite Laggy Pancreatic Enzymes ^
Mycat's mammary gland wase about a centimetre in length s n blackish grey colour and about half of it is thiscolour now.It appears kind ofvattached to the white sectionnow.Ds thissound like mammary cancer?
Aug. 23, 2018
5 Recommendations
Without examining Nickey I cannot (legally) say for certain but any enlargement, change in colour, change of shape of lesions among other signs may be an indicator for mammary cancer; you should get Nickey checked by your Veterinarian to be on the safe side and to get a diagnosis. Regards Dr Callum Turner DVM
Aug. 23, 2018
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birmane
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Zuzu
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1 Month
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5 found this helpful

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My pet has the following symptoms:
Skin Lump
I have a 12 year birmanese cat who was operated 3 months ago for mammary tumor. was sterilized at 10 after complications.Everything went well and the recovery was pretty fast. Also the pre operatory blood tests were all good to the doctors amazement. they asked if i want biopsy but didn't necessary advise to because they said that will only tell you if is malignant or not, but will not change the long term treatment as they consider getting her under chimio would mean unnecessary pain and stress for her and i dont want to put her through that. they gave me some oncologic natural pills, but she refuses them to take no matter how: swallow as it is, powder in the food, diluted with water (i got really scared when i tried that because she started puking and making bubbles at her mouth). now i notice 4 bumps on her body in different places that are growing. 3 are in the skin, not attached to the body. 1 is on her forehead and it attached to her skull. like she just bumped into something and is swollen. she has not lost her appetite and no change in her behavior and i will be visiting the doctor this weekend for consult. but i want your opinion on what should be done next. personally i think some cells migrated and now are growing. what would be the best approach to that?
Aug. 10, 2018

Answered by Dr. Michele K. DVM
5 Recommendations
It is very unlikely that the lumps that you are describing are related to her mammary cancer, as that type of cancer only grows in mammary tissue. It would be best to have her seen, I agree, and have those lumps evaluated to see what they might be and what is going on with her so that a plan can be started for her.
Aug. 10, 2018
My lovely Zuzu died at 5:47 am this morning, next to me. The lumps were swollen lymphatic nodes affected by cancer.I cannot verbally describe the pain of the experience of her passing away, the sound of her crying in her final moments and the twitches of her body trying to breath after her lungs have collapsed. Tonight my sweet Zuzu will sleep alone in the dark. There is no God in dying. No mercy and no after plan.
Aug. 28, 2018
Zuzu's Owner
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tabby
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Beatrice
dog-age-icon
13 Years
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0 found this helpful

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My pet has the following symptoms:
Lump
Open Wound
Infection
I've taken my cat to three different vets. She has a lump on her stomach she wont leave alone, she licks it until it bleeds. They just give me a cone and send me home. It's so big they don't want to operate, but she is alert and doing okay otherwise so they dont want to put her down. Her tumor is now infected and open I treated with antibiotics from the vet for two weeks but it doesn't seem to be healing! I don't know how to help her and the vets wont do anything one way or another.
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Tuxedo
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Dexie
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20 Years
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My cat is 20 years old now. She still eats and moves about, though she seems to be careful about it. She will let me brush her and remove matted wads of hair with scissors but she has given up on grooming herself. A few months ago I saw she had a festering, deep, open wound on her underside between her back legs. I took her to the vet who gave her a steroid shot and gave me ointment to apply to the wound. He said for a cat her age she was really quite fiesty. He asked about possible wounding and I told him that she was our only pet and was always indoors so I felt it didn't begin with an injury. He then mentioned that the location COULD indicate cancer of the mammary glands and recommended I wait to see how she did with the treatment. (At that time she was losing quite a bit of blood from the site.) Today I noticed just a few droplets of blood on the blanket where she sleeps and when I examined her, discovered that the ulcer is back and just as big and just as raw as before. Is it time for me to have my cat euthanized? I love her but I am not able to spend the kind of money that would be required for surgery.
Mammary Cancer Average Cost
From 228 quotes ranging from $3,000 - $8,000
Average Cost
$6,000
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