Featuring Demian Dressler, DVM and Susan Ettinger, DVM, Dip. ACVIM (Oncology), authors of The Dog Cancer Survival Guide.

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Breast Cancer Signs in Dogs?

Breast cancer.

Many have a very strong reaction to these words.  Breast cancer.  How many have a mother, sister, daughter, or friend who have had breast cancer?  Many people.

Breast cancer is very well known in people. But not so much in dogs.

Dogs get breast cancer?  Yes, they do.  We don’t call it by the same name; in dogs we call it mammary cancer, but the mammary gland is the bulk of the body part and the disease is very similar.

Strange that we don’t call it breast cancer in the dog, don’t you think (that is a topic for another day!)

The hardest thing to realize for many guardians out there is that dogs actually have what we would call a breast.  When a mass grows in this area, I have never, not once, heard a guardian talk about breast cancer.

Signs of breast cancer in dogs include the following:

  • small nodules within the mammary tissue (they feel like BB’s)
  • larger nodules within the mammary tissue but still under the skin
  • bloody discharge from the nipple
  • straw colored discharge from the nipple
  • pus-like discharge from the nipple
  • larger, deeper growths in the mammary tissue that protrude visibly and can be seen

Female dogs who have been surgically sterilized (spayed) before their first heat, which is usually around 6 months of age, are essentially free of breast (mammary) cancer.

As the spay age increases, this protection drops.

(It should be noted that early spay is associated with increased risks of other types of cancer however, such as osteosarcoma and transitional cell carcinoma).

It is still debated as to whether spaying once mammary cancer has developed in dogs actually help the problem, and the evidence over the last couple of decades  is mixed at this time.

The most critical thing to remember is that if you have a female dog who has a bump in the area around the teat (nipple), please get it checked.  Many of these growths are life threatening.  And if you have a female dog who is not spayed, or was spayed later in life (at more than 6 months of age), examination of the mammary tissue of your dog may be a life saver.

Breast exam in dogs?

Yes, you heard it here first.  But absolutely, yes, breast exam in dogs who are not spayed or have been spayed late.

How do you do it?

Many dogs like to lay on their sides or back.  This can help but is not critical as a canine breast exam can be done with a dog standing too.

Dogs normally have 10 mammary glands, although you see some extras or some missing here and there as variations. There are two rows of 5 going down the length of the body, one on the left and one on the right.

Find the first teat on the left and right sides.  I use two separate techniques. First, keep fingers flat and fan through the mammary tissue up and down the axis of the torso (head to tail) and feel for “blips”, or bumps passing under your fingertips.  Go left to right as well.

Next, gently press the mammary tissue between the thumb and the index finger with middle finger.  Push your fingers together with the mammary tissue between them and move the thumb across the index and middle finger in a circular motion. Feel for “blips” between your fingers.

How often to do an examination like this on your dog?  I would suggest every month or so for female dogs above the age of 7 years.

Isn’t that about right for a breast exam?

Mammary cancer in dogs is best treated with a combination of different Full Spectrum steps.  In my patients, I use surgery, diet changes, Apocaps, deliberate efforts to increase life quality, reduction in body fat (a risk factor for mammary cancer), immune boosting and other supplements, touch therapies, and more.  This cancer does not respond very well to chemotherapy as a rule.

For more practical tips on diagnosing and treating this condition, check out The Dog Cancer Survival Guide.

Best,

Dr D

About the Author: Demian Dressler, DVM


Dr. Demian Dressler, DVM is known as the "dog cancer vet" and is author of Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog's Life Quality and Longevity. Visit his blog and sign up free to get the latest information about canine cancer. Go to http://www.DogCancerBlog.com.

  • Barb Jones

    Dr. D. I publish a newsletter for the Sussex Spaniel Club of America. Your article on Breast cancer in dogs is interesting and I think would be of interest to our members. In fact we have a member who recently loos a bitch to the disease. May I reprint this article in the October issue of the Scentinel? I could send you a copy of the newsletter if you like. Thank you.

    Barb Jones

    • http://DogCancerBlog.com DemianDressler

      Dear Barb,
      yes, I would be honored to have the article in your newsletter. And of course I would enjoy reading a copy! Send it to my hospital!
      Best,
      D

  • Norine Olson

    Hello Dr D.
    My dog was recently given a diagnosis of having a primary lung tumor.
    Unfortunately due to the location the oncologist said that it was too difficult to do a aspiration of it . Surgery was deemed the only option to beable to do a biopsy of it and the lymph node. An ultra sound was done on her other organs and showed no signs of metastasis. This all came about as a result of finding 3 BB sized tumors in her mammaries upon a typical physical. I had requested an x-ray “before” surgery to rule out any spread. That’s when the Dr found the tumor on her lung lobe. She has no symptoms at present and the Dr feels based on the x-rays that this can be removed with heathy cells dividing it cleanly ?? He obviously won’t know for sure until he gets in there to see any evidence of metastasis . I didn’t see anything about lung cancer and am wondering what your thoughts were on this subject . Also the tumours on her breasts should they be removed at the same time as I am afraid they could be linked even though I was given the 50/50/50 rule by the Dr. Or should I wait to see the biopsy results of the lung first ? Due to longer time under and longer post operative care and pain I am a bit afraid to take that step. I want to do what is best for my dog? What would be your recommendation?
    Thank-you,
    Norin e

    • http://DogCancerBlog.com DemianDressler

      Dear Norine,
      a nodule in the lung does not a cancer make, not by definition anyway. Consult with your vet/onc, but you might consider getting the mammary masses removed and biopsied to see whether the odds of this being a met are high or if those mammary lumps are benign.
      I would take some time to get and read the Guide
      too- I think it will help you with some of these decisions.
      Best,
      Dr D

  • Norine

    Hi Dr Dressler,
    Well I went ahead and got the thoracotomy and removal of the lymph node done on my girl “Miura” who is an just turned 8 year old doberman by the way. She looks and acts 6 ! It was a very scarey time but she was strong and the tube was pulled in 24 hours and she went home on the 3rd day. ( she wanted out of there bad! ) They also removed the mammary tumours. This was all done after consulting with the oncologist and specialty surgeon. They were referred by my regular vet.
    The biospy results came back : Morphologic diagnosis #1 Pulmonary Papillary Adenocarcinoma # 2 lymphoid hyperplasia , hilar lymph node #3 multiple benign mixed mamary tumors,left second gland. #4 diffuse lobular hyperplasia and mltifocal dysplasia, left second and fourth glands. # 5 low grade mastitis both glands.
    His comment ” The tumor in the lung is circumscribed and relatively well differentiated. The decision to call it an adenocarcinoma rather than a papillary adenoma is based on cytologic atypia and loss of nuclear polarity as well as the finding of low numbers of mitotic figures. I did not see evidence of invasive growth, invasion of lymphatics and the hilar lymph node was negative for metastatic disease. I prefer to be optimistic and would suggest a cautiously favorable prognosis. I think a series of radiographs over the next several months is in order. Both glands (mammary) had innumerable foci of atypical hyperplasia and dysplasia which can be considered pre- neoplastic and it could be argued that some of the foci represent in situ carcinomas.
    The oncologist seemed very optimistic and recommended chemo treatment alternating every 3 weeks on 2 different drugs vinorelbine and carboplatin for min 4 treatments to 6 . She started Oct 28,10 and will have a CBC in 10 days
    What are your thoughts?
    I have read your guide and it has helped me alot. She is on the cancer diet started before surgery. I am abit confused though because she is now on chemo what to safely give her ie apocaps etc and what to wait for until after the chemo is done ie omega 3 .Asking the oncologist she remained very “Neutral” Saying nothing has every been proven on dogs but also in theory disproven .
    What would be my next step ? What supplement would you recommend while on chemo ?
    Sincerely ,
    Norine

  • Norine

    Sorry I just realized that I forgot to add the word NOT disproven in the Oncologists thoughts. That would make better sense. :)

  • Kerrie

    Hi,
    My 4 year old bitch had puppies 9 weeks ago . She has started producing bloody discharge from the bottom two nipples. She has a temperature of 103.6 and is on synulox antibiotics after seeing a vet . The vet says she suspects she has mastitis however the teat is not swollen only abit lumpy but apart from that its flat. I noticed bloody discharge is a sign of breast cancer do you think I should be more concerned and question her diagnosis as mastitis, as I have had mastitis in my breeding bitches before and it has always occured afew weeks into feeding pups and they have been big swollen and sort of ropey feeling. This is nothing like that the teat looks normal at a quick glance it is flat but is abit bumpy but not at all red or swollen ?
    Please help
    Thanks
    Kerrie

  • Sweetpea

    Thank you for this article. I have recently noticed my female Chihuahua’s two mammary glands (the one’s closest to the groin) seem a bit firmer and slightly larger than the others. I felt them and they feel firm and one feels like a ball but they do not seem to cause her pain to the touch. I am concerned though because she is 4 years old and i have not got her spayed. ( I intend to soon, i have just found out that getting her spayed protects her from breast cancer. ) I was wondering if you think i should be concerned about her glands? They are not flat anymore and i was wondering if that was because of her adult development or because something is wrong. Could you please give me your opinion.

    • http://DogCancerBlog.com DemianDressler

      Dear Sweetpea,
      I am sorry but I cannot diagnose anything on-line. Please have a licensed vet examine your dog.
      Best,
      Dr D

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  • esther

    my female dog is 8yrs. old . she is a golden retriever and her name is baily. she has breast cancer. lately she has had greyish diarrhea. is this related to the cancer ?

    • Dr. Demian Dressler

      Dear Esther,
      I a sorry to hear about your Baily.
      Diarrhea is a common problem in dogs, and since there are so many causes of diarrhea, it is very difficult to say the cause. Please have your vet work this up.
      Best
      Dr D

  • bella

    HI
    I think my labrador has a breast cancer. the area around one of her nipples is swollen. when i squeezed the nipple a pus-type liquid came out. i asked my father and he said that its normal when she is on heat. but he says that about everything to do with pets. i really want to take her to the vet but my father doesnt because its too expensive. please help!!!
    she is 8 years old and has had one litter of puppies when she was about 4. i hope this helps her.
    THANKYOU!!!!!

  • Shea

    Have diagnosis, just need info: Hi Dr. Dressler,
    My chi has breast cancer that has matastisized and is terminal. She came from a puppy mill and it was obvious that her life before me was a bad one. She already had a lump when I brought her home. Her hips, shoulders, and knees are in bad shape & painful. She actually walks sideways most of the time. Watching her walk is painful; I can’t imagine how it feels to her. I didn’t want a chi but I couldn’t leave her there to be bred with her dad, (the owners hubby let that info slip). It took 3 months just to be able to pet her. She couldn’t stand a large room. I sat in the bathroom floor for hours and just talked softly to her. I have owned chihuahua’s before and was familiar with their charateristics. Of course, I fell in love with her and she is now spoiled rotten and happy–and warm. She loves and trusts no one but me. Her eyes never leave me no matter where we are or who holds her. The cancer is too advanced to warrant the pain of surgery or chemo. She would die anyway. She developes cysts that are painful but usually clear up with antibiotics in a few days. She has developed a lump on the left side of her back with swelling that runs around to her lower abdomen. It is harder than the other cysts. Of course, this developed 4 or 5 days after a vet visit. I am not looking for treatment at this point, (it is too late), but I would like to know what to expect as the stages progress toward her final days. Where does the cancer usually go, what will happen with her when the time is near, how bad is she going to get when she will no longer get better from being sick or in pain. Will it go to the lungs, kidneys, brain, or where. Mom had breast cancer that ended with lung cancer, also went to stomach and kidneys before she died. A friends went to her brain before she died. Rose, (the chi), already has hard, loud breathing. I guess what I am looking for is a sort of road map for the travels this cancer is likely to take and the symptoms I might see as it goes through. I don’t want to call the vet again because I spent a few hours there a few months ago having my beloved Boxer put to sleep, (cardio myopathy), and everyone there was crying over her. They really love the animals they care for. I am sure they are dreading the final time I take Rose in. I just want to know what to expect until that time comes. Thank you.

    • Dr. Demian Dressler

      Dear Shae,
      Sorry this is so advanced. How did this happen that it got so bad?
      I am sorry but this is a question for your veterinarian. Type of cancer within the breast dictates where they go and how they behave. Some spread to the lungs and their is coughing, weight loss, labored breathing, less energy. Some don’t spread except to the surrounding area and these become large and often inflamed and painful. Time again depends on cancer type but without treatment often there is only months in advanced cases.
      I would be at least thinking of diet and supplements here which are low toxicity but can help.
      These are well outlined in the Guide.
      All my best
      Dr D

  • Shea

    She had it when I got her. I couldn’t leave her there to go through this on a hard cold concrete floor with no love, comfort, or a warm blanket to snuggle in. Her puppy days were over so they didn’t want her and were dumping her on anyone that would take her. She didn’t know what to do with toys, treats, or people and didn’t like large rooms or outdoors. I had made the mistake of changing vets because I moved an hour away from mine and that is why I lost my Boxer so quick. Bad, untruthful, in it only for the money vet. I have found that this town is lacking when it come to medical care for human or humane types. I drive that hour if it isn’t an emergency that requires minutes. With the Boxer, it was, but he said she had pneumonia. I even asked him if it could be her heart. With Rose, the chi, the cancer was there and already spreading too far for surgery. I refused the chemo because the survival rate at that point wasn’t enough to put her through it. She has learned to trust me enough that she knows I will try to help her pain and discomfort. When she is in pain, she flips over on her back with her feet up and whimpers while looking at me with those big brown eyes and wrinkled forehead. That means, “I need a belly rub.” I still take her for daily walks but I carry a baby snuggler because she can’t always finish it and my hands sometimes hurts her sore spots. I never know if she can finish it until we get out there. She loves to hike and her best friend is a big 70 lb Boxer that belongs to my son and an even bigger one that lives next door to him, (after me, of course). She is a normal, 7 lb. chi that thinks she is 70 lbs. When I got her she was about 18 lbs on a frame made for a 5 lb dog and the lumps in her breasts were not apparant until she lost some weight. By then, it was too late. I appreciate your response. It was pretty much what I expected, though. She was checked by the vet about 2 weeks ago. This swelling and big lump came up about 4 or 5 days ago tho. I am trying to not be a “hysterical Mom” when I know I am going to lose her anyway. I was almost hysterical over the Boxer and had them that way by the time I left. Even the vet was in tears.

  • Katie

    Dear Dr. Dressier
    I think my female german shepered Brit might have cancer. She has these big bumps on her thighs and two of her nipples are very big. I`m getting worried. Right now we can`t afford a vet so is their anything I ca ndo other than putting her to sleep.

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  • Jay

    Hey dr.
    My female dauchsund was just diagnosed with having a tumor on one of her mammary glands, the vet said it could have been cancerous. She had the surgery the next week and the tumor was removed and the vet had mentioned that it was in the starting stages of cancer. The dog is now home and has been resting now for 2 days since the surgery. After reading a bit more about this problem, i was just wondering if anything else needed to be done. The vet said the dog would be ok, and didnt need any other medication. Could it really be that she is one of the lucky ones, and doesnt need any further attention at the moment, or are there certain medications or steps i should be taking at this point.

    • Dr. Demian Dressler

      Dear Jay,
      one of the most important things is to know if it is benign or cancerous. This is critical since on the one hand you have no cancer, and on the other hand, you have cancer.
      What did the pathology report say?
      Also, did you get your Dach spayed? This may help prevent recurrence or new growths…
      Dr D

  • Charlie

    Im not sure but my jack russell chihuahua mix might have breast cancer she has been scratching her nipples alot and their is little red spots it might be from the scratching though im not sure. She might have fleas and this might cause this but im not wure plEase answer quiqly.

  • Sandy

    Dear Dr.
    I have a bichon frise, 11 months old that was surgically sterilized at the age of 6 months. I´m very worried beacuse i recently found two nodules the size of 2 olivers located on the lower mammary tissue (near the back legs). The nodules had a very rapid growth and i went to the vet yesturday who gave me an anti-inflammatory to administrate during 6 days.The vet told me that the nodules will have to be surgically removed if they keep on growing.
    I just think that it is very strange that my dog has mammary cancer because she is so young and because she was sterilized when she was only 6 months old.
    Could you please give me your opinion?

    • Dr. Demian Dressler

      Dear Sandy-
      yep, thats a bit unusual. they are not inguinal hernias? are they symmetrical (similar position on both sides)- if so the odds of hernias go up.
      D

  • Samantha

    Hey dr i don’t know or I’m not shure but my dog died today I don’t know if she had cancer but her bottom boobies were blue . Be for that she would always play she was always happy but she got sick the blue boobies was one but she couldn’t breath right and she would leave a big old stain of sweat in the covers and she would scream loadly what’s wrong with my dog doctor ?

  • Bijin davis

    hi Dr,
    i need an urgent suggestion from you , i live in India and medical needs for dogs haven’t been well developed for dogs yet. trusting the doctors suggestions and opinions are risky as we just lost our other dog we’ve had for ten years due to their decision.
    The dog i have now , she’s not of any breed, picked her up from the street and she’s been with us for ten years now. She’s been having a small lump or growth on her breast around her nipple. we got it checked by the doctor and he said its a mammary tumor and there’s nothing to worry about. we insisted and asked him if it had to be removed but he still said its fine. it was as small as my thumb. today i had gone out in the morning and suddenly when i came back in the evening its sorta spread around there. i can get hold of that lump by my palm, it was as big as to fill my palm and much softer/wobblier. the small initial lump she had till today morning was rock hard.. and this one now is bigger suddenly in few hours . she didn’t look too hyper so we rushed her to the hospital and the doctor said the same thing ” it must have gotten bitten by some centipede or something there so it looks like there’s an inflammation now , nothing to worry” i somewhat think it really feels like something blasted inside or there’s some sort of leakage inside , under the skin . there used to be a water like discharge lately.

    • Dr. Demian Dressler

      Dear Bijin,
      is it time for a second opinion?
      DrD

  • jasmine

    Dear DR
    MY 7 year old dog has a big lump growing under her nipple area
    She has never been seen my any vet my aunt gave her to me about a year
    Ago do u think a vet will still see her if she has never been checked by any vet?

    • Dr. Demian Dressler

      Dear Jasmine
      yes, a vet will be happy to help. Please get it checked!
      Best,
      Dr D

  • James Bernal

    Hi my 9 year old Jack russel has had two litters when she was young today I noticed her right side second nipple had some brown discharge. I also noticed she had small lumps by her nipple I gently squeezed the lumps letting out a brown discharge. The lumps clearly got smaller as I drained the nipple. It doesnt seem to her her she looked like she enjoyed it. She has not been spayed either. What can should I do, thanks again in advance. James.

    • Dr. Demian Dressler

      Dear James,
      please bring your dog to the vet to get these checked. If you are lucky, it is mastitis (infection). However, cancer of the breast is common in intact female dogs and early intervention is best, so do not wait.
      Best
      Dr D

  • Laura

    my 6yr old chihahau has a yellowish substance coming from one of her nipples. She has had this happen before, it was a different nipple on same side. This time I notice her belly and chest areas skin is turning a blackish color. I am concerned, I can not afford to go to vet, I am already behind in my bills and I don ‘ t know what to do. She has never had pups or been spayed. Please help, or if you know of some orginization that might help low income folks in Macomb county Michigan..

  • Bubbajess

    I have an 11 year old lab with a mass in the glands near her back legs. It was noticed 3 weeks ago. Iv decided against surgery because it wont prolong her life and i would sooner her enjoy whats left. The mass has further lumps around it and it was leaking pus. The vet put her on synulox but it wont clear up. She is showing no signs of pain or discomfort. When that time comes i know i will have to be brave and make the decision to put her to sleep. My question is hiw ling can they live with it and do they show signs of pain. Wgat do you look out for??

  • Georgia

    Hi
    My female Maltese (8yrs) has never had puppies or been fixed. She has a small lump under the skin 2 cm from her 3rd nipple, towards the middle of her tummy. It’s about the size of a pinky fingernail and has smaller lumps around or underneath it. Is there a chance this could be cancer or a fat deposit? I cannot get her into the vet until next week and am really worried. There is no other signs or symptoms and causes her no discomfort. She has a small hernia further down but has never been a problem.
    Thanks.

    • Susan Kazara Harper

      Hi Georgia, You’re right to get this checked out, but there is no problem waiting until you can go next week. (I assume the vet knows about the Hernia.) Nothing major will change in those few days, but your job is to keep an eye on the lump and stay calm and positive. Take a photo of the area, with a coin next to the lumps if they’re visible, then before you go to the vets take another photo with the same coin, for perspective. In the unlikely event that there are any changes at all, these will give your vet a good visual to work with. It is an easy area to aspirate the lumps if you vet or you feel that you want to know for sure. In my book, it’s always better to know, but go with your instincts. Don’t worry. You’ve found it and you’re taking action. That’s the most important step at this time. Give your girl a cuddle from me. All the best!

  • Susan Kazara Harper

    Hi Victoria,
    Well done for noticing this and for asking for information early! It is certainly possible that it is a bite, or perhaps she got caught on something outside. If it appeared suddenly this is very possible. There has been a delay with me responding to you, so you may have already noticed a change. My advise is to keep an eye on it and measure it….. take a photo of th lump with a quarter next to it. In a week take another photo of it next to the quarter. Don’t panic and don’t think the worst. If it remains the same, gets bigger or begins to have any type of discharge, please see if you can get her to the vets for a check-up. You can phone ahead and ask what the charge would be, and maybe get some help with the fee. It should not cost very much for them to just have a look at it, but further tests they might feel necessary could add up. Take it one step at a time. And, well done for rescuing your girl. You’ve given her a wonderful new life, and I’m confident it will be a long one with you being one the ball with your observations. Feed her good, real food, not cheap commercial dog food, and enjoy every day. Good luck!

  • James Alexander

    Thank you for the article – just read while googling for further input. Regarding the comment about “can be done with a dog standing too”, in my own malamute bitch’s case a small lump directly below the nipple could not be felt when standing but was easily detected when on her side: even the slightly larger lump noticeable on/near the surface – which I’d presumed to be possible irritation from grooming in the first instance – was not that easy to detect when standing.
    Lying on the side and checking the uppermost row of nipples, then rolling over and repeating, definitely seems to give a better “feel” for anything unusual than rolled on her back, and certainly vs. still standing.
    Just my 02c, anyhow (and vet consultation to follow on Monday).
    Thanks again & Best wishes to y’all : )

  • kirsty ritchie

    Hi there i have a staf shes 7 and ive noticed a lump in her tit and its been leakin woth all different fluid and now its bloody fluid what could this be could it be cancer?? Many thanks

    • Susan Kazara Harper

      Yes Kirsty, it could. And it could be some other things that could be treated. Please get her to your vet as soon as possible. Good luck.

  • Susan Kazara Harper

    Hi Stephanie, Well, it’s possible that it is mammary cancer, but only your vet can do the test to know for sure. And your dog’s age does not matter as much as how healthy and happy she is. When there is any kind of lump, the best action is usually to cut it out, so if your vet feels that your dog is OK with surgery, please consider it if you can. If is is a cancer, diet is very important, and you can find the best Dog Cancer Diet on the main blog page. Good luck.

  • Susan Kazara Harper

    Hi Roxanne,
    Get her to the vet. Nothing can be determined online, she needs an exam, and in the meantime you are only worrying. That’s just wasted effort and doesn’t help either of you. Make the appointment please and once you know what’s going on, you’ll have a better focus. Good luck!

  • Susan Kazara Harper

    Hi Aaron,
    Well done for finding these differences.
    It would be irresponsible to offer an opinion online for your girl, and at best would be only speculation anyway. You’re doing the best thing by making that vet appointment. Don’t delay. Good luck.

  • Susan Kazara Harper

    Hi Lewis,
    Best thing to do is to get her to the vet. No one should attempt to diagnose online, yet we’re here for you once you know what you’re dealing with. We always do recommend getting all lumps and bumps checked without “waiting to see”. As to whether cancer can be diagnosed without surgery, there are ways. Many vets with a lot of experience can give you a good idea, but without at least a needle biopsy, where they draw out cells from a mass and put them under the microscope, it’s difficult to say for certain. You would also need to know the type of stage of any cancer to determine a treatment plan. This cannot be done without getting cells through a needle or a small piece of tissue being taken. Do let us know if there is further informaton now, and if we can help you untangle any of it. All the best.