Eight Early Signs Your Dog May Have Cancer

Many people do not realize that cancer is not just a human condition; it can also affect your pet. Recent research from National Canine Cancer Foundation indicates that in every three dogs, one is affected by cancer. This makes cancer the number one killer disease of cats and dogs. Cancer affects both purebred and mixed breed dogs. Some types of cancer can occur at any age, but cancer is especially common in older dogs. Today, we will examine eight of the most common signs of cancer in dogs.

1. Abnormal swellings that persist in growing

The most obvious sign of cancer is a mass of lumps or bumps that continue growing on or under the skin. As a general tip, dogs’ bodies should be symmetrical throughout, meaning that one half of the face and body should be approximately equal to the other. So looking over the dog to determine if he is symmetrical can help in spotting if something is irregular or asymmetrical. If you find any irregularities, consult your vet immediately for an examination. If it turns out to be benign, this is great news for you and your dog. However, if it is malignant or cancerous, then you may be able to catch it before it spreads.

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2. Diarrhea or changes in bathroom habits

 If your dog experiences occasional diarrhea, it does not automatically mean that it has cancer. However, if this condition persists, you need to go to a vet for an examination. According to PetMD.com, when your dog starts begging to go to the bathroom and has difficulties when peeing, starts vomiting or find blood in its stool or urine, your dog may have cancer. Remember, blood in the stool isn’t always red, and black stools or rust-colored urine indicate that blood is likely present. If you find any of these symptoms, consult your vet immediately.

3. Abnormal discharge and seizures

Another cause of concern is persistent discharge from eyes or nose. Persistent nose discharge is a common sign of facial tumors whole the eye discharge may be an indication of an eye tumor. Seizures are common signs that indicate brain tumor. This is mostly found in older dogs. When you start noticing sudden and uncontrolled bursts of activities such as chewing, foaming at the mouth, or jerking of the legs, your dog may be seizing. Consult your doctor immediately.

4. Lethargy or Depression

Although depression or lethargy is not a symptom that is immediately related to cancer, accumulation of symptoms related to these conditions are season enough to speak to your Vet. Consult your vet when your dog start sleeping more, less willing to eat food, less playful or less willing to go on a walk.

5. Sudden Bad Breath and Oral Bleeding

Dogs generally do not have pleasant breath, especially as their age progresses. However, their breath should not be horrifically bad. Tumors growing in the mouth can trap saliva and food, leading to secondary infection, which may result in terrible breath. Additionally, when a dog develops tumors in the mouth, you may start noticing difficulty in eating as well as bleeding after eating.

6. Big belly and bleeding

As your dog ages, it tends to gain a bit of weight. However, waking to find your dog with a bulging belly should raise an alarm. Researchers say that the growing of tumors or ruptured tumors can cause the dog’s abdomen to suddenly appear enlarged, and bleeding is likely to follow. The most common causes are cuts or trauma. However, if you find your dog bleeding from the genitals or nose, you need to take him to the vet clinic for an examination.

7. Limping or collapsing

As your pet becomes old, you may find him limping, especially after vigorous activities. However, the limping should stop after a few days. If you find your dog limping for more than a week, take him to the nearest pet clinic for evaluation to determine whether if it is from arthritis, infection, bone cancer, a ruptured tumor, or another health-related reason. If your dog collapses, it should be treated as an emergency.

8. Loss of appetite as well as difficult in eating or swallowing

If your dog has intestinal cancer, the dog may feel a mass pushing along the intestine, making it harder to keep an appetite. The dog will then stop eating and begin to appear weak, followed by sudden weight loss. Additionally, you may notice your dog having trouble swallowing or chewing. Also, a cancerous lump that may have developed in the neck can put pressure on the esophagus, making it difficult to swallow.


Early detection of cancer is paramount. While there is no need to become paranoid, you should be informed and keep your eyes open for these symptoms. It is also wise to take your dog to the vet for regular checkups. This will help you to catch cancer or other conditions at early stages before it is too late. Additionally, regular checkups help you to keep your dog happy and healthy for a long time.


IMy name is Evelyn Valdez, creator of PlaywithMeow! I love all pets (especially cats) because they always make me happy and healthy. I want to connect with other pet lovers in the world to share experience in healthy and caring pets

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