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Top 10 Signs of Cancer in Dogs and Cats

Top 10 Signs of Cancer in Dogs and Cats

Many people do not realize that cancer is not just a human condition — it affects our pets as well. In fact, cancer is the number one disease-related killer of dogs and cats.† Dr. Lorie Huston tells her clients to be on the lookout for the following signs. While these symptoms are not purely indicative of cancer, if a pet begins to exhibit them you should visit your veterinarian immediately. Just like with people, the earlier cancer is caught the better.

10. Lumps and Bumps

Not all lumps and bumps on or under your dog or catís skin will be cancerous, but there is no way to know for sure without getting your veterinarian involved Ė this is especially important if the lump is not resolving itself or is growing in size. A needle biopsy is commonly done and a veterinary pathologist can let you know if the cells are cancerous or not.

9. Abnormal Odors

Offensive odors from your dog or catís mouth, ears, or any other part of your petís body, should be checked out. Oftentimes cancers of the mouth, nose, or anal regions can cause such foul odors.

8. Abnormal Discharges

Blood, pus, vomiting, diarrhea, or any other abnormal substance being discharged from any part of your petís body should be checked out by your veterinarian. In addition to that, if your dog or catís abdomen becomes bloated or distended it could be a sign of an accumulation of abnormal discharge within the body.

7. Non-Healing Wounds

If your pet has wounds or sores that are not healing, it could be a sign of infection, skin disease, or even cancer.

6. Weight Loss

Cancer is among the list of diseases that can cause weight loss in a pet. If you notice sudden weight loss in your dog or cat (and it is not currently on a diet), along with other signs from this list, be sure to mention it to your veterinarian.

5. Change in Appetite

Dogs and cats do not stop eating without a cause. While a lack of appetite does not automatically indicate cancer, it is still something to be discussed with your veterinarian. Oral tumors can also cause difficulty or pain when eating or swallowing.

4. Coughing or Difficulty Breathing

Coughing or abnormal breathing can be caused by heart disease, lung disease, and also cancer. Cancer can metastasize through the lungs and cause these symptoms.

See Also: Dog Food Allergy Myths

3. Lethargy or Depression

If you notice your pet is not acting like itself Ė sleeping more, less playful, less willing to go on walks or to exercise Ė this can also be a sign of cancer. Once again, lethargy or depression is not a symptom confined to cancer, but an accumulation of any of these signs is reason enough to speak with your veterinarian.

2. Changes in Bathroom Habits

Changes in your petís urinary or bowel habits Ė difficulty using the bathroom, frequent bathroom use, blood in urine or stool Ė these are all potential signs of cancer.

1. Evidence of Pain

Limping or other evidence of pain while the pet is walking, running, or jumping is mostly associated with arthritic issues or joint or muscle diseases, but it can also be a sign of cancer (especially cancer of the bone).

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4:13AM PDT on Oct 10, 2014

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2:56AM PST on Dec 28, 2013

this is very interesting. Our cat had a large tumour and had to be euthanized, but even the vet appeared not to have noticed it when he took out several teeth under anaesthetic three weeks before. Yet, there were odours and some of the other signs, which I had not equated with cancer. I will be more vigilantt next time.

10:47AM PST on Dec 24, 2013

So sad.
One my cats died of cancer and to this day I ask myself if her pills for birth control was to large dose for her tiny body size. All cats get the same dose no matter if they are huge or tiny.
We operate our cats to prevent that they have kittens . I operated her when she was old, and I regret the pills I gave her.

3:46AM PST on Dec 24, 2013


5:27AM PST on Dec 22, 2013

thank you

4:46AM PST on Dec 22, 2013

They need our attention even to the tiniest things

3:50AM PST on Dec 14, 2013

thank you.

8:28AM PST on Dec 5, 2013

FYI my dog got very stinky..out of her pores, not a specific place. She did not ever like her tummy rubbed, and it turns out she had multiple breast cancer tumors so I did not find the lumps until one bled…then we went straight to the vet --no kidding-- we were there 15 minutes later. She was 15 years old which still was amazing for a dog her size…a tall slender 60 lbs.

8:36AM PST on Dec 2, 2013

Thank you ! Lost my 18 year old cat to cancer. Nobody noticed but I saw that she was breathing slightly different. She had been to the vet 2 weeks before and everything was fine then. They offert me to drean her longs so I could keep her a bit longer. But loved her enough to not make her suffer any longer. We shared 18 beautiful years of close friendship and I'm greatful for that.

4:30PM PST on Nov 28, 2013

thank you

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