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
- weight loss
- loss of appetite
- 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.
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. Demian Dressler is internationally recognized as “the dog cancer vet” because of his innovations in the field of dog cancer management, and the popularity of his blog here at Dog Cancer Blog. The owner of South Shore Veterinary Care, a full-service veterinary hospital in Maui, Hawaii, Dr. Dressler studied Animal Physiology and received a Bachelor of Science degree from the University of California at Davis before earning his Doctorate in Veterinary Medicine from Cornell University. After practicing at Killewald Animal Hospital in Amherst, New York, he returned to his home state, Hawaii, to practice at the East Honolulu Pet Hospital before heading home to Maui to open his own hospital. Dr. Dressler consults both dog lovers and veterinary professionals, and is sought after as a speaker on topics ranging from the links between lifestyle choices and disease, nutrition and cancer, and animal ethics. His television appearances include “Ask the Vet” segments on local news programs. He is the author of The Dog Cancer Survival Guide: Full Spectrum Treatments to Optimize Your Dog’s Life Quality and Longevity. He is a member of the American Veterinary Medical Association, the Hawaii Veterinary Medical Association, the American Association of Avian Veterinarians, the National Animal Supplement Council and CORE (Comparative Orthopedic Research Evaluation). He is also an advisory board member for Pacific Primate Sanctuary.