Top 10 Warning Signs of Cancer in Dogs and Cats

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May is Pet Cancer Awareness Month, a time to spread awareness of the symptoms of cancer in dogs and cats. As cancer is the leading cause of death in cats and dogs, knowing the symptoms your pets may present if they develop the disease can help you and your vet diagnose and treat your pet sooner. In order to help you protect your pet’s health, has pulled together the top 10 warning signs of cancer in dogs and cats.

1. Lumps and Bumps: Not every lump or bump is necessarily cancerous, but consulting with your vet is the only way to be sure. If the lump is growing or not resolving itself, contact your vet and he or she will do a biopsy to determine the contents of the bump.

2. Abnormal Odors: Foul odors from any of your cat or dog’s orifices and/or body parts may be a cause for concern. Cancers of the mouth, nose, or anal regions can cause your pet to emit offensive odors.

3. Abnormal Discharges: Discharges such as blood, pus, vomit, diarrhea, and any other abnormal substance being excreted from your pet’s body should be checked out by a veterinarian immediately. A bloated or distended stomach could also be a sign of internal discharge.

4. NonHealing Wounds: Lacerations or sores that do not heal within a normal time range on the surface of your cat or dog’s body may indicate infection, skin disease, and possibly cancer.

5. Weight Loss: Sudden weight loss in cats and dogs not on a diet can be an indicator of many diseases and illnesses. If coupled with another warning sign of cancer, you should contact your vet right away and inform him or her about your pet’s symptoms.

6. Change in Appetite: While a lack of appetite in dogs and cats can be an indicator of many things, they never stop eating without a cause. Not necessarily a sign of cancer, a decrease in appetite can indicate an oral tumor, which would make it painful and difficult for your pet to eat and swallow.

7. Coughing or Difficulty Breathing: Although symptoms of heart and lung disease, coughing and abnormal breathing can also indicate cancer. This symptom will most likely occur if the cancer in your pet’s body has metastasized into his or her lungs.

8. Lethargy and Depression: If your pet has cancer, there is a chance that he or she will suffer from depression and sleep more, become less playful, and be less willing to go for walks. Although lethargy or depression in dogs and cats can set in with any illness, it is commonly seen in pets that have cancer.

9. Changes in Bathroom Habits: Any changes in your pet’s bathroom habits including difficulty using the bathroom, frequent bathroom use, and blood in urine or stools are potential warning signs that cancer has developed in your pet.

10. Evidence of Pain: Limping or other evidence of your dog or cat in pain when he or she is active, or if the pain is too great for them to be active, can be indications of cancer of the bone.

While no one sign purely indicates cancer, a cat or dog displaying two or more of these symptoms should be taken to the veterinarian for an exam so that he or she can be properly diagnosed and treated accordingly, because early detection can make all of the difference in the case of a positive diagnosis.

46 thoughts on “Top 10 Warning Signs of Cancer in Dogs and Cats”

  1. My Golden Retriever “Samson” just got diagnosed with cancer in the lymph nodes. He’s 10 and I’d like to have him around longer but I’m struggling on what’s the best thing for him is right now…

  2. Our German Shepard lab mix has all of a sudden in the past couple of weeks developed a big bump on his back right leg. I am hoping its not something too serious cause I can not afford a vet visit or bill.

  3. I gotta question for those of u who r dog lovers. I have a husky he sheds every summer. Lately he hasn’t been eating very much. I can tell he has lost weight. He sleeps a lot but whenever we take him outside he runs round and goes crazy. I’m just worried cuz he doesn’t eat like he use to and he looks sad. The only symptoms I see, don’t eat much, loss weight n sleeps all day and runs round all night

    • If you can’t affor to take your pets to the vet I’m sorry to say then you shouldn’t have them. It isn’t fair to them. It you can’t take them to a vet or feed them or whatever needs to be done. We have 3 dogs and no children. They are taken care of as if they are our kids.

      • Just had my 12 year old lab die with cancer in her throat ,Yes she went to the Vet many times and every year for shots Also treated for CHF for almost 3 yrs ,Makes me sad that some people love Pets and don’t have the money to take them Pet meds and vet visits cost more than human health visits

  4. Please don’t moralise with people who are heartbroken/worried sick about a pet they love while not having much money. Maybe their pet gives them immense comfort when they don’t have much else to hope in at present. They’re company and are deeply loved. Losing them is one of the hardest things to bear and the tears that can flow for many years are hard enough to cope with. Animal charities exist in some countries for those who can’t afford regular vet’s bills. They may depend on donations or provide much cheaper alternatives. Some may require proof of income if on benefits/state aid (due to a job loss perhaps? Nobody judges there anyway) Humanity, please! Pets are grateful creatures who may feast on scraps of food if necessary. They’re loved and lovable…as are the people who love them to the end.

  5. My gorgeous wolf dog got cancer he was 12years old. We did not know at first that he had it as he was stiĺl acting like a puppy most days. He started limping on all fours and his breath was smelling badly, we thought it was just old age. He started being extremely tired and not himself. He was moulting a lot and I noticed 3 lumps under his fur. when he stopped eating his favourite things and drinking more water I took him to the vet’s. Thinking he would be ok little did I know. The vet checked him over and said he had aggressive cancer and had to put him to sleep. The thought of losing my best friend was unbearable but the vet said treatment would not work. I miss him every day but knowing he is not in any pain was the kindest thing to do.


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