Pet Cancer Awareness Month: 10 Must-Spot Signs of Cancer in Dogs

Pet Cancer Awareness Month: 10 Must-Spot Signs of Cancer in Dogs
17 Dec 2016

Cancer is a scary word, but a dangerous one to ignore. Early diagnosis of pet cancer gives your four-legged companion the best chance of licking this disease. And that’s what Pet Cancer Awareness Month is all about: Raising awareness of the signs of cancer in dogs and cats, and understanding there are options for treatment.

What are the Chances?

Where cats and dogs are concerned there’s good news, and there’s bad news.

First, our canine companions:  The bad news is dogs aged 10 years are over stand a one-in-two chance of developing cancer at some point in their lives. However the good news is that many canine cancers are not aggressive.

OK, so for our feline friends: The good news here is that the rate of cancer is much lower than in dogs. But the bad news is that when cats do get cancer it tends to be of the aggressive sort.

Signs of Cancer in Dogs

If you own two dogs, statistics say one of them will get cancer during his life. This throws into sharp focus why it’s vital to be aware of the signs of cancer in dogs. So as part of Pet Cancer Awareness Month let’s take a look at 10 Must-Spot Signs of Cancer in dogs.

Cancer in Dogs

Do not be alarmed if you pet shows some of these signs, but do get them checked by a vet. Remember these signs can be caused by issues other than cancer, but they remain important clues that your dog needs to see a professional.

#1: Swellings:

Check your dog over once a week for lumps, bumps, and swellings. Get any new ones checked by your vet (and see #2 below). Sometimes the vet can give you a quick answer, by harvesting a small sample of cells via a needle and examining them under the microscope.

#2: Changed Lumps:

Measure your dog’s existing lumps and write down their size. Check them once a week, and also be alert for any changes in the firmness and shape of the lump which could indicate skin cancer. One of the signs of cancer in dogs is rapid growth or change texture, and this should always prompt a trip the vet. 

#3: Persistent Pain

Pain is a warning that something is wrong, so be alert for restlessness, whining, or limping. Bone cancer in dogs is especially painful and the signs include swelling and the dog flinching when the area is touched.

#4: Bad Smells

Sometimes cancerous tissue becomes infected and this can lead to a bad smell. If your dog smells offensive take the hint and have them checked.

#5: Altered Toileting

Many signs of cancer in dogs are associated with a change from what’s normal for that individual. If your dog develops persistent diarrhea or strains to pass urine, these changes of toileting habits should serve as a warning of possible, bowel, prostate or bladder cancer.

#6: Loss of Appetite

Don’t underestimate the significance of a poor appetite in a dog that loves their food. This disinterest may happen and you can tempt the dog with a novel tit-bit but then he loses interest. If this is out of character then be sure to take this seriously, especially if your pet loses weight.

Signs of cancer in dogs

#7: Weight Loss

This often goes hand-in-paw with #6 above. If you’re concerned about your dog’s appetite, weigh him regularly and keep track. If the trend is downwards then off to the vet it is.

#8: Lack of Energy

This one of those vague signs of cancer in dog that shouldn’t be overlooked. Fair enough if you have an older dog he might just be slowing up and not want to go for long walks, but does his lethargy also extend to things that used to get that tail wagging? If life is a struggle and getting out of bed is an effort…well, get him checked.

#9: Heavy Breathing

Sadly lung cancer in dogs is a “silent” disease because the tumors in the chest grow quietly, not causing symptoms until they squash the lungs. If you notice your dog’s breathing has changed and is either rapid and shallow, labored, or he’s developed a cough, then keep him quiet and get a vet check for problems including lung cancer.

#10: Thirst

Some cancers give off chemicals which cause tissue death and toxin release, which makes the dog thirsty. If you can, collect a sample of the dog’s urine and take it along to the vet check, as it will help to start ruling other problems out.

And finally, whilst these signs of cancer in dogs may seem scary, know that an early diagnosis gives your pet the best possible chance of recovery – and the odds are often excellent. The worst thing you can do is ignore the problem and hope it will go away. So this Pet Cancer Awareness month – be just that – Cancer aware.

To promote pet health, during the month of May, you can enroll of the First Aid and CPR course (plus access to our webinar sessions) for just 29.00. To take advantage of this offer visit and enter the code HEALTHYPET.


Pippa Elliott

Pippa Elliott, BVMS MRCVS, is a veterinarian with 27-years' experience in companion animal practice. Pippa's first job was in a practice by the sea, where she acquired her first (of many) waif-and-stray, a Dockyard Cat Rescue kitten, called Skate. She then worked for the PDSA (People's Dispensary for Sick Animals) which is a national charity that provides veterinary care for the animals of owners with limited finance. Currently Pippa works in a Veterinary Clinic in UK.