12 warning signs of cancer in dogs that every owner should know

The idea that our four-legged best friend might be sick is terrifying enough without the dreaded diagnosis of cancer. But just as with humans, spotting the signs early and getting your pup to the vet for a treatment plan is key. Whether you’ve found a fatty tumour on your dog or you’re suspicious that you’ve got a case of dog skin cancer on your hands, keep an eye out for these signs of cancer in dogs to help you identify a problem early.

Here are 44 secrets your veterinarian won’t tell you.

If your dog collapses, get to the vet immediately. Collapsing, weakness and general lethargy (not greeting people at the door like usual or less interaction) are common signs of cancer, says Jake Zaidel, DVM, of Malta Animal Hospital in upstate New York. “I see this particularly in large breed dogs – even if they fall down and seem better the next day, bring them in because it could signal a tumour of the spleen,” says Dr. Zaidel.

Coughing doesn’t automatically signal cancer; for example, small breed dogs tend to develop coughs because they have windpipe problems. “If the dog coughs once or twice, it’s of no concern, but if it continues to cough for more than a few days, that’s a concern and could signal lung cancer,” says Zaidel.

Here are 10 other  noises your dog makes – and what they mean. 

Weight loss is the number-one dog cancer symptom Dr. Zaidel says he sees. It’s often the sign of a gastrointestinal tumour. “I’ve had a lot of dogs stop eating because of gastrointestinal tumours, so they lose weight very rapidly,” he says. Cancer can also cause dogs to lose weight while maintaining their regular appetite. If you notice your dog shedding weight, either rapidly or slowly, make an appointment with your vet.

Here are 12 foods you didn’t know could kill your dog. 

Sores, lumps, a strange odour, bleeding or a change in gum colour can be a sign of oral cancer, particularly in older dogs. This cancer sign in dogs often goes unnoticed for too long. “We commonly find visible oral tumours because people don’t examine their pet’s mouth,” says Dr. Zaidel. “Many oral tumours can be really devastating because people don’t find them until it’s really advanced.” He also suggests brushing on a regular basis.

It’s a good idea to watch when your pet yawns or eats, advises Timothy Rocha, DVM, an oncology specialist in New York City. See a vet if you notice something out of the ordinary.

Nosebleeds are never normal, says Dr. Rocha. “With an older dog, a nosebleed is particularly worrisome. It can be a sign of cancer in the nose,” he says. “With younger dogs, I would worry more about something like a foreign object stuck up there before cancer.”

Occasional diarrhea usually isn’t a sign of cancer in dogs, says Dr. Rocha, but if it persists or gets worse, get your dog to the vet. Constantly begging to go out to go to the bathroom, difficulty peeing/moving bowels, vomiting or blood in the urine or stool are also potential dog cancer symptoms, according to PetMD.com.

These are 22 bathroom mistakes you never knew you made. 

Persistent discharge from the nose or eyes is cause for concern, says Dr. Zaidel. Nasal discharge is a common sign of facial tumours and eye discharge can signal an eye tumour.

Here are 6 ways to make your dog smarter. 

Seizures can be a sign of brain tumours and are typically seen in older dog cancer patients, says Dr. Zaidel. If you start to notice sudden and uncontrolled bursts of activity, like champing and chewing, jerking of the legs or foaming at the mouth, your dog could be experiencing seizures and you should see a vet immediately, according to WebMD.com.

“Every lump, bump or skin change should be checked,” says Dr. Zaidel. “It could be benign or cancerous, but it’s always easier to treat the earlier it’s caught.” Feel for bumps, lumps or swelling as you pet your pooch. If you notice something iffy, don’t delay – there’s no way to distinguish between a lump that’s benign or malignant without taking a sample. Also, pay attention to any sores that won’t heal or lesions that seem itchy or painful.

These may also be signs your dog has fleas.