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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Persian
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Fluffy
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10 Years
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2 found this helpful

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My pet has the following symptoms:
None So Far
Hello, My cat is a 10 year old female Persian (She was spayed when she was 8). A few months ago I noticed she had a lump on her stomach. She had surgery to remove it and the dr discovered another one that he removed as well on the day of. They were sent to a lab but the dr did not fully explain the report of the lab, so I was wondering if someone can explain it a bit more. The masses were: 4*3*2 cm & 2.5*2*1.5 cm. Diagnosis: mammary gland masses intraductal carcinoma and infiltrating ductal carcinoma. Sections from both masses reveral malignant spheroidal cells showing hyperchromatism, pleomorphism and enlarged nuclei. They are arranged in masses, islets and sheets. There are some ducts lined by malignant cells and forming cirpriform pattern. The tumor tissue is close to the lateral and deep surgical margins in both specimens. She also had an xray before her surgery and her lungs were clear and her blood work was fine. She did not show any sign of illness just the lumps. If a Dr. can explain this report I would be very grateful. And also from what is written in the report what steps would you hypothetically advise to take, and any idea about average life span would be appreciated. I know no confirmed prognosis can be given without examination, but any information and advice would be truly appreciated. Thank you.
Aug. 1, 2018

2 Recommendations
Your Veterinarian should have explained to you the histopathology report and advised you on any follow up care that may be needed: “intraductal carcinoma and infiltrating ductal carcinoma” is indicating the type of cancer and the location/origin (started growing in the milk duct and spread into the surrounding tissue); ”Sections from both masses reversal malignant spheroidal cells showing hyperchromatism, pleomorphism and enlarged nuclei. They are arranged in masses, islets and sheets. There are some ducts lined by malignant cells and forming cribriform pattern” indicates the morphology of the cells in the sample which the Pathologist observed in order to make the diagnosis; “The tumor tissue is close to the lateral and deep surgical margins in both specimens” indicates that the surgical margins were narrow and some tumour cells were found near the margin of the ‘healthy’ tissue when excised. From the report I cannot give any indication of prognosis and would recommend consulting your Veterinarian regarding follow up care since Fluffy is under their duty of care. Regards Dr Callum Turner DVM
Aug. 2, 2018
Thank you Dr. Callum for your response, much appreciated.
Aug. 3, 2018
Fluffy's Owner
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Siamese
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Sushi
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11 Years
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My pet has the following symptoms:
Nipple Swelling, Clear Discharge
I have an 11 year old beautiful Siamese/domestic mix cat. she has been dealing with some ankylosing spondylitis for the last three years and we have been giving her steroid shots for the last year every 3-4 months. They tend to perk her up and give her strength. The last two haven't done much justice. She got her last injection of steroids on Monday of this week. She had been more lethargic, sleepy and laying around a lot more. NOt really wanting to be around people that much. Tonight I came home from work and was rubbing her belly and found a irregular cystic lump around one of her nipples. I showed my husband and he squeezed it a bit and we noticed clear fluid coming out of the nipple. no erythema or warmth noted around said nipple, just discharge. it has been expressed and size has been decreasing since expression. Do I need to worry this is mammary cancer? Ductal papilloma? Thanks for your help!
July 20, 2018
0 Recommendations
Without examining it and possible sending a sample off for histopathology I cannot say for certain what it is; if there was some discharge from the nipple I would recommend visiting your Veterinarian for an examination to be on the safe side as I cannot give you any assurances without an examination. Regards Dr Callum Turner DVM
July 20, 2018
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American Shorthair
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chelsea
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14 Years
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My pet has the following symptoms:
Vomiting
what should I feed my cat who is 14 and has mammary gland cancer? she is not eating very much and I want to make sure that what she does eat is healthy for her.
July 16, 2018
0 Recommendations
There are a lot of people online recommending numerous different diets for cancer in cats, however Tuft’s university checked 27 online diets and found that they didn’t meet the basic nutritional requirements for their intended species; it is important to find a balanced diet suitable for Chelsea which she will accept as there is no specific ideal diet just one that she will eat. If she isn’t eating you may want to encourage appetite by mixing some smooth wet food with a little water and syringing it into her mouth; alternatively some wet foods if heated slightly are more appetising due to an increased smell. Regards Dr Callum Turner DVM http://vetnutrition.tufts.edu/2017/08/cancer_diet/
July 17, 2018
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european
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Akira
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6 Years
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0 found this helpful

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My pet has the following symptoms:
No Symptoms
Hello, I need your opinion for my cat, a wonderful 6 year old tortoise shell. I took her to the vet immediately after feeling little nodules on her belly. She had surgery a month ago and her mammary chain has been removed. She had several little nodules, superficials. The biopsy revealed that this was an adenocarcinoma, with moderate mitotic activity, and that the lymphatical node is healthy. The x-rays didn't reveal any metastasis. My vet advised me to remove the other mammary chain, but didn't talk about chemotherapy. Unfortunately I noticed today that she has a new nodule, very little (2mm) on the other mammary chain. I hope there is still time to save her... Do you think that the fact that the cancer restarts at the other side is a sign of aggresivity? Or maybe juste because both mammary chains received the same hormonal impregnation? Her surgery is programmed on the 19th of July. I don't want to give her another surgery, if the chances to cure this cancer are weak... Thanks for your help...
July 6, 2018

0 Recommendations
It would be good to have the other mammary chain removed regardless, I know this is a stressful time for you but I cannot give you any assurances that there hasn’t been any further spread of the cancer without further histopathology and x-rays to check again for any secondary tumours. The use of chemotherapy in cases of mammary adenocarcinoma is generally unrewarding and radical mastectomy is the treatment of choice. Regards Dr Callum Turner DVM www.vin.com/apputil/content/defaultadv1.aspx?meta=&pId=11147&id=3846248
July 7, 2018
Thank you. She will have her surgery very soon. It's dificult to be optimistic, i only read bad experiences, this is a terible cancer. Do you think that it's posible to cure this cancer if treated very quickly ? My vet sayed it's posible. I will try everything to save her, she could live many years more...
July 7, 2018
Alex F.
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DOMESTIC
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Snickers
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11 Years
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My pet has the following symptoms:
Normal Behavior, Lumps Along Mammay
My cat Snickers had a cancerous tumor removed from her mammary chain about a year ago. The lump was removed and there were no cancer cells present after the surgery. A few months ago, I noticed to additional lumps along the same mammary chain. I now plan on having both of her mammary chains removed by surgery and going from there. We are going to the vet next week but I'm very nervous that the cancer has already spread to her lymph nodes or lungs. How likely is it for the cancer to spread to her lymph nodes or lungs after a year (when the post surgery test showed nothing)?How quickly can that happen?
July 1, 2018
0 Recommendations
It really depends on the type of mammary tumour among many other factors; there is a risk that there is spread to regional lymph nodes or other organs but it is difficult to stay statistically as there are many variables. Your Veterinarian will be able to tell you more based on their findings. Regards Dr Callum Turner DVM
July 2, 2018
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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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