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

Signs of Dog Cancer and Decompensation

Updated: November 22nd, 2018

People are often stunned to find out their dog has cancer. Why? Because cancer seems to hit out of the blue. I often hear “but he’s been fine until the last couple days!” In this article, I’m going to take just a minute to explain why “cancer” seems to happen overnight. (Hint: it’s because of dog cancer decompensation … not cancer itself.)

“Signs of Dog Cancer” Are Really “Signs of Dog Cancer Decompensation”

Search for the warning signs of dog cancer, and you’ll find plenty of listicles that include items like the following:

  • a new lump that is hard
  • a limp
  • coughing
  • weight loss
  • loss of appetite
  • vomiting
  • diarrhea
  • thirst changes
  • bad breath
  • yellowing of the skin or eyes
  • abdominal swell
  • difficulty breathing
  • spontaneous bleeding
  • unusual odors

But those are not signs of cancer. They are signs of dog cancer decompensation.

Your dog has had cancer for a lot longer than you realize. The signs listed above are actually signs that your dog’s body has stopped being able to compensate for cancer, and her body’s normal functions are breaking down.

Looking back at your dog’s last few months, or even year, you might think I’m crazy.

How is it possible that a dog can act totally happy, eat, drink, move around, socialize … and have cancer?

Don’t sick dogs act sick? Well, let’s take a look at that.



Decompensation Defined

The clearest definition of decompensation I’ve found is this:

“Decompensation is the functional deterioration of a previously working structure or system.”

Every organ and system in the body function well under normal circumstances. And every organ is designed to have lots of built-in safety systems so that if something goes wrong, the organ can STILL function while it repairs itself.

So, when a medical problem is introduced, the body can “compensate” for it. Let’s take a non-cancer example.

Say you are using a hammer and hit your thumb. That’s our medical problem: your bruised thumb.

The tissues immediately swell up. That’s the immune system sending fluid to the area both to keep it from moving too much (which could further injure it), and also to bring white blood cells to the area to start helping repair the damage.

Your immune system is “compensating” for the medical problem by sending help.

Now, normally, your thumb would heal in a few days or a week. You might not even really notice the thumb’s hurt, after a while.

But let’s say that you damaged your nail very badly in the strike. The body simply can’t repair the damage done. After a week or so, you might find your nail falling off. Now it takes months for your nail to grow back in.

Well, that’s your “decompensation,” right there. Normally, you have a nail on your thumb. But now, you don’t. Your body could not compensate for all the damage done.

So now you’ve got a clear sign … for months … that you have been damaged, and that things aren’t normal.

When Safety Systems Fail

When your dog has cancer, her body will kick in all sorts of safety mechanisms (depending upon where the tumor is) to keep the body working properly. Dogs act normally during this time.

So do people, if you think about it. You probably know someone who has had cancer. Did they feel terrible right at the beginning? No … we don’t start really noticing symptoms until cancer has disrupted our health. Until our safety systems start failing.

So what we see listed as the “signs of cancer” are not really signs of cancer at all. They are signs that cancer has gone past a certain tipping point.

They are signs of dog cancer decompensation.

They are signs that cancer is in a late stage.

In other words, once a dog starts to act sick, it’s already late in the game.

What to Do If Your Dog is in Decompensation

If your chest is tightening as you realize that your dog isn’t “suddenly sick,” but may have had cancer for a while, please take a few deep breaths.

This is a difficult concept to accept, and it’s totally normal to feel, well, to feel awful about it. Just because we usually find cancer late (after decompensation) doesn’t mean that we can’t do anything about it. There are lots of things to do to help your dog’s life quality and even optimize longevity.

So if you haven’t had a diagnosis yet, get one. Knowing what you’re dealing with will help you to make decisions. And if you do know it’s cancer, don’t be afraid to get a second opinion, just to make sure. Any professional vet will be okay with this, and it wise to double check to make sure the dog cancer journey is a path you are on.


Get the Dog Cancer Survival Guide to read more on End of Life and Hospice Care, in Chapter 25


Bottom Line: Test Healthy Dogs for Cancer

The fact is that one out of two dogs over ten gets cancer, and one out of three overall get cancer. It’s the number one killer of dogs at this point. So we should all be taking it very seriously, and testing dogs for cancer, earlier, when they seem healthy.

Starting in the last quarter of life at the earliest, get annual (or more frequent) imaging done to look at internal organs: X-rays, ultrasounds, etc. Don’t ignore lumps and bumps, but get fine needle aspirates, biopsies. Blood and urine tests can serve as critical screening tools.

When’s the last quarter of life? There’s a comprehensive list in my book for breeds and their average life expectancy, but you can also base it on weight:

  • Dogs up to 12 pounds live approximately 14 years, so start annual testing no later than 10.5 years.
  • Dogs 12-30 pounds live approximately 13 years, so start annual testing no later than 9.75 years.
  • Dogs 31-50 pounds live approximately 12 years, so start annual testing no later than 9 years.
  • Dogs 51-80 pounds live approximately 11 years, so start annual testing no later than 8.25 years.
  • Dogs over 80 pounds live approximately 9 years, so start annual testing no later than 6.75 years.

The reality is that when caught early, cancer is easier to treat and we have better chances of preserving life quality (and even extending longevity).

Best to all,

Dr D



 

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  1. MMN on June 21, 2010 at 5:12 am

    Research Curcumin. It stops cancer growth, and is miraculous.
    Suzanne Summers even wrote about it in her book Knockout….

  2. gloria alexander on January 20, 2010 at 3:59 pm

    I too feel it is extrememly important to no have any grain…my dog was diagnosed with bladder cancer 2 years ago last September. God knows how long she had it before I realized she had blood in her urine. She had 8 rounds of chemo as well as Piroxicam daily. She is still the Piroxicam. I had her on Hills Cancer ND at the time…high fat is very important…no, no, no carbohydrates…NONE…NO PEAS, AND NO CARROTS…turns to sugar…bad carbs. ONLY BROCCOLI OR GREEN BEANS. I supplemented her and still do with 4,000 units of Omega 3,6,9. 1 Mannose cap, 1 cranberry cap, this helps to prevent the urinary infections.
    I believe it is truly a miracle that she is still cancer free, I am so, so lucky to have her….I treasure every moment I have with her. She is the glue that holds me together through life.
    I now have her on only raw ground beef,(once in a while cooked chicken) I buy the best I can, mix with 2 tablespoons of cottage cheese, 1 1/2 tsp. of wheat germ, 1/3 can of salmon or fresh salmon I grill and only a hand full of Orijen kibble—grain free for the crunch she needs for her teeth. NO NO GRAINS!!!!

  3. sandra lovitz on January 20, 2010 at 9:06 am

    All of you should try Transfer4Life supplements. This makes the dogs
    already amazing immune system work five times better…all the steroids, radiation, chemo, accelerate the situation. These supplements are by 4LIfeProducts. http://www.4life.com ….this is not your typical “western” method of treating cancer. One thing is what all vets recommend.. take your animal off of ALL GRAINS. I am currently
    doing this. My dog had a tumor removed on his leg 8 months ago…
    so far.. I don’t know if this will work, but I am hopeful and will not subject my animal to the cruelty of chemo and radiation.

    • Dr. Dressler on January 22, 2010 at 10:01 pm

      Dear Sandra,
      I was interested in checking out, but could find no data in the portion of the site tabbed “science”. Can you provide the readers with some objective information about this product? Specifically it’s application to cancer (preferably dog cancer, but human is okay too..).
      They would be very interested to know!
      Thanks
      Dr D

  4. eva on January 20, 2010 at 8:14 am

    My 9 1/2 yr old Rottie, Boots has lymphoma. We didn’t notice until he started losing weight rapidly. He is on prednisone to shrink the lymphoma, It has worked a bit, he’s gained a little bit of weight this week. We opted for no chemo. It’s also in his blood. He’s doing ok, he has a good appetite & still runs at the park. We take our 3 dogs to the park every day…if it doesn’t rain too much. We’ll keep him with us till he doesn’t feel well. He loves people & has always been very confident. I’ve been giving him more omega 3 & vit c also. I am going to make sure my other 2 dogs have regular check up, they’re both 5yrs old.

  5. phillip on January 19, 2010 at 6:12 pm

    Susan, Thank you for your message and kind remarks. My male Golden
    retrievers name is Gibson. He is 7 years old. I’m from Garden city,
    Michigan, in Wayne county. I’m not exactly sure what Apocaps is, but
    I’ll look into it. Feel free to email me. psdouglas141@juno.com
    God bless Phillip

  6. Susan on January 19, 2010 at 1:34 pm

    Phil, I feel for you. If you can get the mix of ingredients contained in Apocaps, please try them. Our boy did so well on them. I can’t help but wonder if you can get to another vet who would be willing to try surgery. If your dog is getting weaker, surgery won’t be an option much longer. But you have to decide how you feel about it. If a vet understands you want to try to remove all or part of the growth to give your dog relief, knowing the risks, your opinion should be respected. Your dog (I don’t know his/her name) may not make it out of surgery, but then again, it may. It’s a fine line and a scary decision. Bless your heart, I’m thinking of you both. Please let us know your dog’s name so we can send some special thoughts out.
    Bottom line, what is your dog telling you? You know him or her better than anyone. I think the thing we all hate the most is to think that our dog is holding on just for us. But when you look in those eyes you’ll know what he or she wants. Without a doubt, your dog knows how much you love.

  7. Susan on January 19, 2010 at 1:21 pm

    To everyone out there helping their dogs fight cancer – – I’m with you. Don’t stop. Don’t stop questioning and fighting and doing everything you can. Sometimes our wonderful vets look at the inevitability of a disease and approach us with the “it’s kinder to realize the truth now than to live in false hope” attitude. But you know what? Our Shadow was given 2-3 weeks to live, and we had seven wonderful months of him being very happy, active and loved. Our vet was amazed that he was doing so well. Shadow still left us much too soon, but he taught us to learn all about a good diet, natural supplements, and making sure he had joy around him every day. Please read Dr. Dressler’s book – the knowledge is priceless for all our animals, not just those with a diagnosis. Don’t stop. Don’t stop. Don’t stop. When your vet gives you an opinion, ask for a test to show you the proof. If your gut feels that you want to know more but you don’t want to question your wonderful vet – QUESTION. You are the only voice your dog has, and any vet worth the qualification should respect your need to KNOW.
    For those of us who have loved and lost, the fight continues. Stay on board. Let’s help everyone else out there with encouragement, love, and as much support of Dr. Dressler’s research as possible. Dog cancer should not be a death sentence. Humans are beating the odds because of knowledge; early detection and good treatment. Our dogs can do the same. My Shadow taught me so much, and I will not let him be a single chapter in my life. He’ll be here to help me help others.

  8. phillip on January 19, 2010 at 9:34 am

    Dr. Dressler,

    Months ago, I took my golden retriever in to have a lump in his abdomine
    checked out. My vet told me to keep an eye on it after his examination. He
    thought that the lump was most likely a non cancerous tumor. After a couple
    months went by, I noticed that the growth had got quite a bit bigger, so I took
    my dog in again. My vet tried to use a needle test to try to extract a sample,
    but the growth was so firm, that he could not get the needle to penetrate, so
    he made an incision instead. After viewing the growth from inside, he told me
    that my dog had a growth called fibrosing streatitis myositis. I was then sent
    to a specialist who did a much larger incision to extract some inner samples
    of the growth to be sent out to a lab. The biopsy came back as spindle cell
    sarcoma. A surgury was recommended to remove the tumor, but I was told
    it would be risky because of the tumors size and location. I decided not to have
    the surgury performed. Weeks have passed now, and the tumor is quite huge
    and firm. It fills in both sides of my dogs abdomine, and underneath. His hind
    leg is now suffering from swelling and lameness. Because the tumor is seeking
    more territory, it is now pressing against his organs and stomach, causing total
    lack of appetite, and the ability to hold solids down. My vet recommended a
    half cup of ensure twice a day. I also add some ground up chicken or beef to
    the ensure. I have to totally feed him with a spoon, then holding his mouth some
    what shut se he does not spit the food out. He is also losing weight quite rapid.
    (I forgot to mention something earlier). Please read on. I was told that the tumor
    is now starting to press against my dogs areas, that will soon effect his ability
    to urinate and pass a bowel movement. This is the latest from my conventional vet.
    My dog will not eat on his own anymore, but he is drinking water. I’ve tried Artemisinin,
    cantron, milk thistle, proteo enzymes, IP-6 Inositol, liquid herb detoxifiers, multiple
    vitamins, fish oil, and so on. I considered giving him neoplasene taken orally, but
    was told that neoplasene could cause complications because of the tumors size,
    and possibly leave a hollow hole once the tumor was attacked. The cancer is far
    along, and I’m feeling like my options are running out. I’m considering 2 last options.
    Apicot seeds, B17 along with B15, or Essiac tea capsules, ( Ojibwa herbal blend),
    or something from the cancer fighting strategies site. I would deeply apprieciate
    your opinion on these options, and my general email. I’m also concerned that
    this form of cancer may be so far along at this time, that no magic bullet or
    supplement will work, and that maybe I should just see my vet to give him a
    peaceful exit, but at the same time, If i can find something out there that will
    shrink the tumor and give my dog a little longer to live, It’s worth pursuing.
    If not, I have to say that I’ve at least given a good fight concerning my dog.
    Phil

  9. Patti on January 19, 2010 at 6:29 am

    My yellow Labrador Retriever, Ian, was also taken by hemangiosarcoma at age 11. At the advice of the vet at the time, we opted for no chemotherapy. I then acquired Ian’s half-brother, Conor, (the result of cryogenic artificial insemination). Conor is also a yellow Labrador Retriever. His cruciate ligaments blew out in both knees at 18 months, then he developed iris cysts and was diagnosed with mast cell cancer at age 9. As much as I hate to admit it, it just seems like the entire gene pool of many of these breeds is now corrupt. It’s heartbreaking. Where did all of these maladies come from all of a sudden? Is it the flea/tick preventatives? Vaccines? Foods?

    • Dr. Dressler on January 22, 2010 at 10:43 pm

      Dear Patti
      well, to be honest I devoted the first part of my book to answering that question. Aside from the obvious breeding and in-breeding issues (it may be time to start thinking about getting away from propagating certain breeds…you heard it here first folks and don’t start throwing tomatoes quite yet), we live in civilization. Part and parcel of this choice and inevitability are the diseases of civilization. We are seeing the effects of modern society on our dogs as a reflection of ourselves on earth.
      Dr D

  10. Anita on January 19, 2010 at 4:06 am

    The last quarter of life is too late to be doing these tests. I’d say the last half of a dog’s life is more appropriate. My dog, Casey, was a yellow Labrador Retriever who died at the age of 8 after a 2 1/2 year battle with mast cell cancer (diagnosed when she was 5 1/2, and which is not what killed her) and hemangiosarcoma (diagnosed August 2009 when I found a lump on her neck — she collapsed on December 13, 2009, and was euthanized). Casey was on chemo (cyclophosphamide, Piroxicam) and had had a clean ultrasound on October 3rd. Her expected life span was something like 12-14 years. She was a Therapy Dog at Children’s Hospital in Cincinnati. It was a huge loss to a lot of people when she died. I am now writing a book on her life to raise awarness of hemangiosarcoma.

    Anita Eisthen

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