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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tabby
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Kenya
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11 Years
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My pet has the following symptoms:
Lumps
My female cat is 11 yrs old. She had 2 lumps removed from her abdominal area several days ago. She didn’t show any of the signs of being ill other than the 2 lumps I found around her abdominal area. She was very active as usual and her appetite was hearty. After the surgery, she is just laying and occasionally walks around with me. I figure she is still recovering from the surgery and is quite sore. She still has 2 days left if her pain meds for swelling and about 5-7 days for her nerve pain. My vet just called me this morning after receiving the report on her testing of the masses removed. She has mammary cancer. Im planning on getting her treatment and will consult a specialist that treats cancers such as this. I broke down upon hearing the news. I have 2 cats, both sisters. They are a joy and life in the House. Well, my question(s) is/are: since I’ve had the 2 masses removed, what are her chances of not having any more cancerous masses growing? Also, will treatment still be needed even if no cancerous cells develop? If they are dormant, will chemo/and or another form of treatment eliminate the cancerous growths whether they are active or dormant?
June 20, 2018
0 Recommendations
Mammary cancer is an umbrella term for different types of cancer both benign and malignant, however the majority of mammary tumours in cats are malignant (around 80%); without knowing the specific type of cancer found it is difficult to give advice, however the Oncologist will be able to tell you more after examining her and reviewing the histopathology report. Regards Dr Callum Turner DVM https://vet.osu.edu/vmc/companion/our-services/oncology-and-hematology/common-tumor-types/feline-mammary-tumors www2.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/mammary-tumors
June 21, 2018
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Domestic shorthair
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Nala
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13 Years
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My pet has the following symptoms:
Open Cancerous Ulcers On Mammaries
Hello, My domestic shorthaired cat was diagnosed with mammary cancer a year ago. They told us she would probably only live another year unless we got the entire mammectomy done, but my father refused to pay the amount toward the surgery. She now has open sores on her abdominals, which are oozing. And I want to keep them clean and wrap her up but I’m not sure how. She is full of life, walks around just fine, eats and drinks like normal. My sister thinks we should put her down but I can’t seem to decide which is the better decision considering she acts like a happy, normal cat. I’m sure she’s in some pain from the cancer and sores, but It’s such a tough decision. Do you think we should keep the area clean for now and wait until she gets worse, or would it be best/more moral to put her down considering the circumstances?
June 4, 2018
0 Recommendations
Once mammary tumours start ulcerating, there is little else to do apart from surgery (which it appears is not an option); bathing the ulcers with a dilute antiseptic and removing any discharge is not a long term solution. However, you need to decide whether you should continue to bathe the ulcers/sores or if you will decide if it is time for euthanasia. Regards Dr Callum Turner DVM
June 5, 2018
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Maine Coon
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Kusia
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13 Years
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My cat is turning 13 years old this summer, and I recently noticed a few small lumps around her mammary glands. At first, they were extremely small. I took my cat to the vet and she told me that a biopsy is usually inconclusive but, if they're cancerous lumps, surgery may not be recommended at her age because the cancer could spread regardless. I was told to keep an eye out for changes in lump size and changes in behavior. The lumps have grown. And there MAY be nipple discharge. But so far no noticeable changes in behavior. What would you advise I do? Would a biopsy be a good idea after all? Would it tell me anything other than whether or not it's cancerous? And would surgery to have the lumps removed be a good idea if it is? I'm not sure how long her life expectancy is and if surgery would do enough to keep her healthy.
May 29, 2018

Answered by Dr. Michele K. DVM
0 Recommendations
Some mammary cancers are benign, and only cause problems because they grow. If you are able to have the masses removed and sent away for pathology, that would give you the most information, and give Kusia the best chance at not having the lumps continue to grow. It is much easier to remove those masses when they are small. If your veterinarian does not want to remove them, it may be worth seeking a second opinion to see if another veterinarian thinks it might be a good idea, since I cannot examine her.
May 29, 2018
My mom's cat just passed away last weekend. We found a lump in her breast in October 17. The biopsy came back cancer. So my mom said no agressive treatment, it isnt going to do anything anyway. She never had another tumor, I think the cancer spread inside of her. She just stopped eating, and became really skinny and passed away.
July 7, 2018
Lorraine C.
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tabby
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Porsha
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13 Years
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My pet has the following symptoms:
Lump
My cat is 13 years old female sterilized and found a lump on breast in November/December 2017, the vet I saw then said it's not hurting her and if she's eating fine then just to keep an eye on it and nothing about spread or an x-ray. Fast forward towards end May, I wanted to have her lumps removed at another vet clinic and they said it has already spread to the lungs and about a 1cm spread and just to be sure it's not an inflammed lymph node. The report came back that it's a heterogeneous 2.65mm x 2.55mm so I was already prepared and was told she's got 3-6 months left since it's already spread. S Thinking and focusing on alternative methods, I decided to consult with a close to holistic vet and she couldn't get any documents and upon checking my cat's lung and stuff, decided she wanted to do her own x-ray and then consulted with told me she asked 3 of her colleagues opinion and they all agree there is no spread and she's not as sick and able to do surgery. Previously, her surgery was cancelled since it spread to her lungs and she wouldn't do well under anaesthesia and if she does, she might be really sick or worse after. My question is, which is right? What is going on? One doctor saw it on x-ray and another says it's not there and even though she read the chest ultrasound, she said it's not accurate and inconclusive. Holistic vet also said, can't give her a 3mths-6mths to life since she is not seeing what they did. Furthermore, the vet who first did the x-ray and canceled the surgery, said that lung symptoms don't show till the lung is 50% compromised and while the holistic vet said she heard no wheezing and shows no signs of lung symptoms nor do her xray show a cloudy parts which is what is normally seen in a spread to the lungs from the breast. A metastasis. Then what was the ultrasound showing at 2cm ++ x 2cm ++... Very confused
May 9, 2018

Answered by Dr. Michele K. DVM
1 Recommendations
Without seeing her test results, I'm unfortunately not able to shed much light on what might be going on with Porsha, unfortunately. I think that you need to decide which of the veterinarians that you have seen you trust more, and ask for more information. There are board certified specialists that can look at x-rays and ultrasound results and give a second opinion, and it might be a good idea to start there, to sort of get an unbiased opinion on the x-rays and ultrasound results, as that seems quite pivotal in all of this. I hope that she is okay.
May 9, 2018
I should have added that I'm not in US or Canada so I'm not familiar of board certified specialist with unbiased opinions. The question is, is there something else that could be showing up in the ultrasound? My vet sees the other clinic's xray and says, she still sees it on their xray. The holistic vet is new and I have not consulted with her before so I have not developed trust with her at this moment. She seems more interested in getting a CT scan going ahead with the surgery that its not a big operation and making it seem like a light situation but my regular vet says that the stress to the lungs due to the anaesthesia,she might not wake and if she does, not do so well.
May 9, 2018
Porsha's Owner
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Bengal
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TRENDAR R U MY SUNSHINE
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7 Months
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My pet has the following symptoms:
Acting Normal
my breeding Bengal has been 3 strong heats. she is not yet 8 months old. She has been beside but I am certain not with a male. After 4 days strong calling, I used the q tip method to take her out of heat. since then she has had small lumpy circular firmness around her teats. I have massaged it and pinched it,This is not tender. Do you think she may be having a hormone thing, making some milk or is it something worse? should I havve a hormone level test done? can any vet do this?
May 3, 2018

Answered by Dr. Michele K. DVM
0 Recommendations
It does sound like your cat is having a heat cycle, and mammary development can occur with those hormone changes. If the behaviors and mammary development continue, it would be best to have her examined by a veterinarian to determine whether she is having a problem or is having a normal heat cycle. They'll be able to assess her and recommend any necessary testing that she may need.
May 4, 2018
My 10 year old neutered cat was diagnosed with aggressive breast cancer in October 2016. She had a full mastectomy incl removal of the lymph nodes. Sadly we noticed in early February little pea sized hard modules including under her throat area. Two of the 5 lumps (so far), have grown extremely fast and are about 3 to 4 times larger. Cat went back to Vet for checkup and biopsies last Monday. The result came back and she not only lost 800 g of her weight despite great appetite, but all modules are secondary tumours. Nothing can be done anymore as it has gone into the lymph system bar giving her lots of TLC. Vet subscribed Metacam to treat any pain. We wonder what her lifespan under this is going to be - truly devastated
May 4, 2018
Lora
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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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