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How Do You Know If a Cat has Breast Cancer?

May 22, 2011

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Tinkerbell is a calico long hair kitty

Tinkerbell waits for surgery to try and cure her cancer

What is This Lump on My Cat’s Belly?

Tinkerbell needed help. The 14-year-old long-haired calico cat looked at Doc Truli with calm eyes. She even purred in the examination room! Tinkerbell had a tumor growth on her belly. It felt bad. Knobbly, bumpy, fluid-filled pockets of firm roundness in a 6 cm area in the middle of her right mammary chain. Not good. The lump did not hurt and it was not broken open or infected, but it just seemed a matter of time before she started suffering painful consequences.

Feline mammary adenocarcinoma in this case feels like bibles of tight fluid pockets on the belly of a cat

Mammary Adenocarcinoma

There was one confusing, hopeful fact, however. According to Tinkerbell’s mom, Katherine, the tumor had been there for years. Years! Doc Truli knew that metastatic breast cancer in cats usually behaved aggressively – meaning it spread fast and far in the body. But here was TInkerbell with this lump growing for years. Maybe it was not a spreading type of tumor?

“Doc,” said Katherine,” She’s 14, I don’t know if I should put her through surgery at her age.”

How Old is Too Old for Major Surgery?

Many people worry about doing too much invasive medicine or surgery on an older pet. Now, I do not agree that a 10 or 12-year-old cat is old. Or a 10-12 year old Shih Tzu or Chihuahua. A 12-year old Great Dane or Boxer is old, but it all depends of the breed of the patient and their known expected lifespan. Doc has known plenty of 18-20 year-old cats. 14 just didn’t seem that old for Tinkerbell.

Truli Speaking

“I do not agree that a 10 or 12-year-old cat is old,” says Doc Truli.  “An 8-12 year-old cat I call young-old.  12-15 is middle-old.  15 and up is ‘bonus rounds.’  You really have to know your cat.  Are there other diseases that prematurely age your cat, like diabetes or hyperthyroidism or renal insufficiency?  No?  Then why can’t your cat live  20 or 25 years with a little luck?  I believe many cats die too young because their people think they are old and because of the perception that it’s a lot of money to spend on a cat and because of fear that the medicine or surgery will not work, people decline medical care for their cats.  The cats suffer from this medical pessimism.  It’s a shame.”

“If there are no other illnesses apparent on the minimum database testing, and her chest x-rays screening for cancer metastasis are clear, then I believe the surgery is worth it,” said Doc Truli. “Even a benign tumor can grow too large and rupture open, making a painful, infected mess. We need to avoid that outcome for Tinkerbell.”

Minimum Database

Have you heard your veterinarian say “minimum database?”  It means a complete blood count, 25 chemistries of the blood including electrolytes and urinalysis.  The medical standard of care is a minimum database on every sick patient ever time they come to the hospital in order to know the internal status and diagnose correctly.  In cats, many specialists consider the feline leukemia and feline aids virus tests to also be part of the standard-of-care minimum work-up.

In an emergency room, the minimum database has to be fast.  An ER MDB usually consists of electrolytes, BUN, creatinine, blood glucose and PCV (measure of anemia).  The other test take too long when seconds count to save a life.

Tinkerbells’s Big Surgery Day

Tinkerbells’s pre-op lab tests and radiographs were normal. She came for the big surgery day. To help minimize pain and bleeding, her mom elected the upgrade to Laser surgery for her lumpectomy procedure. The Laser cauterizes blood vessels and nerve endings as it cuts with invisible energy beams. The tumor lifted nicely off of the light yellow, slightly greasy subcutaneous fat. The hole sewed up neatly.

A close-up of the laser cutting the skin around the tumor

A closer view of the Laser at work on the tumor

Then Doc felt a lymph node in Tinkerbell’s armpit. The problem is: normally, you cannot feel cat axillary lymph nodes. Normally they are too small to feel. Doc Truli performed an excisional biopsy of the lymph node, which means removing the whole lymph node for testing to see if it contains cancer cells.

You cannot feel a normal cat armpit lymph node.

Tinkerbell recovered perfectly from surgery and was eating and purring a few hours later.

What is a Biopsy and How is a Biopsy Processed at the Laboratory?

The only way to know for sure if a lump on a cat’s body is cancer is a biopsy. A biopsy means removed a piece of cat and fixing it in poisonous formalin solution and shipping the sample of your cat to the reference laboratory (usually in another state) for a board-certified pathologist to analyze the lump. The lump is sliced into pieces about 1/2 cm across and placed in a special holder called a “Cassette.” Most laboratories will use paraffin (special wax) embedding to preserve the piece of your cat. The gigantic 1/2 room-sized paraffin embedding machine runs for 12 hours to embed the cassette with your cat’s lump in it. Usually these “runs” are done overnight to let the machine work while the laboratory staff enjoys some sleep time at home. (So, if your sample arrives on time for the evening prep and run, you’ll be a day ahead.  If it misses that night, it has to wait 24 hours for the next “run.”)

Tru Tip
Have your veterinarian write “board certified only” on your laboratory request form. In the United States, there is a shortage of board-certified veterinary pathologists, so unless you specify, a board-eligible or resident-in-training may read your sample. Perhaps they will have enough knowledge to help your cat, perhaps not! Pathology is a highly skilled, highly interpretive specialty. You always want the best you can get!

In the morning, the cassettes are taken out of the machine and sent for sectioning. A person physically sits at a machine called a microtome that resembles a tiny table saw crossed with a sewing machine crossed with a razor blade. The technician cuts your cat’s lump into 4-5 millimeter sections. (You can see through 4-5 mm!) They gently lift the 4 mm slice off the machine with tiny steel forceps and float the see-through slice on the surface of a bowl of just-under-boiling hot wax. Once the slice turns color and has interacted with the wax, it is lifted off of the wax and laid flat on a glass microscope slide. After the see-through prepped piece of cat tumor sets and dries, it is stained through a multi-step process and stored for the pathology specialist to examine it under a microscope. (Doc Truli spent a summer at a microtome doing this job to benefit brain cancer research.)

So, next time you wonder why you have to wait “so long” for results, just remember what it takes to get an answer for you and your cat.

Pre-op picture of how little tumor showed above the fur (about 2 cm around). You could feel it was large under the skin (about 6 cm around).

This tumor is the "tip of the iceberg," you have to feel around under the skin for these cancers on your cat.

What Are the Options for a Cat After Cancer Diagnosis?

Tinkerbell healed completely after her surgery.   Unfortunately, the results came back “malignant mammary ductal adenocarcinoma with metastasis to a regional lymph node.”  So, on the one hand, that’s a back diagnosis.  We know that no amount of chemotherapy or radiation therapy really helps this kind of cancer in cats.  On the other hand, it also is supposed to grow fast and kill fast, yet she had the lump for years before it grew to a bothersome size.

Tru Tip

If you have an older cat, Vitamin E (no researched dose, some vets use 100IU/day), Omega 3 Fatty Acids at a dose of 180 milligrams of the eicosopentanoic acid (EPA) subcomponent per 10 pounds of cat per day, and Probiotics for cats (get at a vet clinic or a reputable on-line natural products dealer) will only help.  There are very few medical conditions that these supplements will hurt.

We decided to leave Tinkerbell alone.  We boosted her nutrition with kitten food and probiotics, Omega 3 Fatty Acids and Vitamin E, with the idea that good quality nutrition would help her body do whatever it was meant to do to try and stay healthy.  We have no scientific evidence that herbs or other remedies would help in the case of cat mammary cancer.  Plus, being a cat, Tinkerbell did not accept a lot of “messing with.”  It’s a fine line between making a cat do something you know is good for them, and stressing the cat out so much that they get sicker from anxiety and displeasure.

Tinkerbell accepted her new diet and supplements and is going strong all these months after surgery!

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17 Comments leave one →
  1. February 24, 2015 12:51 am

    What ever happened to to Tinkerbell? Is she still alive? If not, how many years/months did she live after this surgery? My cat is having a similar surgery this week. Thanks

    • February 24, 2015 8:54 am

      Dear CZ,
      Tinkerbell did well and lived several more years. Your question regards “prognosis. ” It is perfectly reasonable to ask your vet for a prognosis for your cat. It is your vet’s best educated guess based on science and your cat.
      -Doc Truli

  2. October 18, 2014 10:36 pm

    My cat has a large, hard breast tumor that has ruptured, and another long, spongy tumor on her belly. Our vet has refused to operate because she is 18 and in kidney failure. Is there any way that the ruptured tumor could be removed with local anesthesia? And do you have a recommendation on whether I should consider putting her down? I’m concerned because the vet said that this may heal, but will open again, and I don’t want her to suffer.

  3. March 27, 2014 10:37 am

    Thanks so much for this article, it’s the first one I’ve seen about an older cat with a tumor. We have a cat that might have breast cancer, but the vet doesn’t know. It’s a long hard lump that runs from one nipple to the other and is relatively thin(a few millimeters thick). They aspirated it, but it was inconclusive(they think mostly because it’s too thin to get a good sample). They’ve tried antibiotics to rule out infections, and that caused no change. It basically appeared overnight, as being on her stomach we feel it every time we pick her up, so it could not have been there long before we noticed it. Now after about three weeks it hasn’t changed. The vet advised waiting to see if it changes. His biggest concern is her age – she turned 15 last November. So he doesn’t want to do unnecessary surgery on her(if it’s not cancer).

    However, the whole thing is making me crazy. I just don’t know what to do, I check the lump daily to see if it changes(and of course it does based on how she’s sitting or laying). As of last night I think it might be thicker than it was, so now what do we do? Is 15 1/2 too old for the surgery? She’s been healthy otherwise, just a couple pounds overweight is her biggest concern, and UTIs about 10 years ago. Otherwise she doesn’t have health problems. But I don’t want to put her through this surgery if she’s not likely to fully recover. I’ve had her since she was a kitten, and am having a really hard time imagining life without her. I had really hoped she’d make it to at least 17. I don’t want to give up on her and not fight for her, but I don’t want to make her life miserable with surgery if it won’t make her life better.

    So I guess my question is would 15 1/2 be to old? Would we be better waiting to get a good diagnosis before surgery? Have you ever heard of a cat having long thin tumors instead of a lump? Is there anything else we can do to try and find out what’s going on?

    Thanks again for any help you can give.

    • March 28, 2014 2:30 pm

      Dear Beth,
      Yes, long thin tumors are possible.
      No, no way to tell if 15 is too old and if surgery will shorten her life.
      No, biopsies without just removing the thing are not recc’d b/c it may just spread like crazy.

      So, that said, if you want a diagnosis without extensive surgery, maybe your vet could remove a nugget of the lumps with local anesthesia?

      Also, if she is bright and youthful in every other way (other than the lump) maybe she’ll do well with surgery.

      Another thought-the lump is a part of her, albeit a troublesome part. If you categorically do not want surgery for her, perhaps a local talented alternative medical veterinarian would be able to guide you.

      Doc Truli

      • March 28, 2014 3:05 pm

        Thank you so much for the reply. We aren’t against the surgery – other than the fear that it will make things worse for her. We want to give her the best quality of life we can, and if surgery will do that – we are all for it – I’m just worried about making things worse for her.

        Our vet suggested that he could do the surgery but was concerned that at her age she may just get some other age related disease in 6 months and die anyway, and then we made her miserable by putting her through surgery. Where-as I’m hoping if we need to do the surgery she’ll live at least 2 more years. She still seems so young to us, the only sign of aging she has is the fur on her ears is thinner then it used to be, and she doesn’t like to jump on higher furniture(but that might be the extra weight).

        We’re not in a big city, and I don’t think we have any alternative medical vets for at least 5 hours from here, and she hates car trips. I would love to get her something like that though.

        Thanks again, for this, It has given me hope.

  4. Alex and Fluffy permalink
    September 7, 2013 1:48 pm

    How much did this cost? I don’t want my kitty to die.

    • September 7, 2013 6:09 pm

      Best to schedule a consult with a veterinarian you trust. Commit to the initial physical exam and consult fee. Then ask for a written cost estimate for everything else.

      Good Luck!
      -Doc Truli

  5. Ashlynn permalink
    August 27, 2012 1:27 pm

    My cat Beatrice is around 10 years old. Our old neighbors left her when they moved out. We took her in and have had her for a year in a half. We just found out today that she has breast cancer. She also is a diabetic. What do you think the life expectancy would be for a cat who is a diabetic and has cancer if we decide to go through with the surgery? They are not sure if it has spread but they did note that her lymph nodes were a tad enlarged. She has a bladder infection right now so i am not sure if the enlargement could be from the infection. Much like Tinkerbell she has had the lump since we found her. I started to notice another small lump though as well. She had xrays done and it shows that it has not spread to her lungs. The doctors said they would need to remove the breast tissue on one side and the lumps. I am worried about her and am not sure surgery would be beneficial for her. Most stories I am looking up the prognosis is not good even after surgery. Thank you for your time.

    • August 28, 2012 7:15 am

      The question of prognosis is specifically part of your veterinarian’s job to estimate for you.

      Depending on her physical and tests, I have seen cays live for weeks after surgery. And I have seen cats live for years. It is partly a question faith in making the decision for surgery

      The diabetes complicates the picture considerably. I would 1) clear up the uti 2) treat the diabetes. Possibly her diabetes will resolve. The cancer could spread if you delay. On the other hand, she could have trouble healing properly if you rush surgery.

      Go with your instincts and your vet’s advice. There are no “right” answers.

      Good luck. You will choose the right path.

      -Doc Truli

  6. Stacey permalink
    March 18, 2012 11:26 pm

    My cat won’t stop meowing and she only uses her litter box when she fells like it she would go in my bathtube instead

    • March 25, 2012 9:01 am

      Stacey, please take your cat to the veterinarian. She is acting distressed.
      -Doc Truli

  7. May 22, 2011 10:00 pm

    Very informative post, and the backstory and photos helped explain all the steps involved between exam and path results. Ps: Noticed the correction on Sphynx, too 🙂

    • May 29, 2011 10:52 am

      Hi Teri!
      Thanks for your feedback, as always! I just realized your blog is, but your cats barely have any fur! What’s the story, there?
      Doc Truli

      • May 29, 2011 10:07 pm

        Hi Doc T,

        Hahameow! Some explanation IS needed. The Furry Dance is a spring festival that has been held in Cornwall since the 1500’s and when I began breeding Cornish Rex (which originated in Cornwall) I picked for my cattery name, Furrydance. Cornish Rex do have wavy fur, though some are quite sparsely coated. The Sphynx can be sparsely furred, like peach fuzz, although my Sphynx, Disco NoFurNo, grows fur on his tail and in random clumps on his body…it is quite variable in the Sphynx as to how naked they are.

      • June 1, 2011 7:23 am

        Fantastic Teri!


  1. How to Tell If Your Cat is in Pain « VirtuaVet

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