Skip to main content

Worried your dog has cancer? Be on the lookout for these 8 symptoms

Dogs are called “man’s best friend” for good reason. Whether your pup is an entertaining clown or a dignified protector, the bond between a pet parent and their fur baby is unbreakable. Unfortunately, dogs aren’t immortal — or even immune to one of the most insidious diseases: cancer. Early detection is the key to a good prognosis, so we’ve consulted the experts and compiled a list of the eight most common cancer symptoms in dogs. The more knowledgeable you are about the warning signs, the more likely you’ll realize something is wrong with your pup before it’s too late. Here’s what to look out for.

A closeup of a black and white dog.

What is the most common cancer in dogs? 

According to, breast cancer is the most common type in humans. But it differs for our canine companions. The most common types of cancer in dogs are:


Often found in the heart and spleen, hemangiosarcoma typically remains undetected until the disease is in an advanced stage. Unfortunately, this is also one of the most rapidly advancing types of cancer, which forms blood-filled tumors.


Canine lymphoma is almost identical to non-Hodgkin’s lymphoma in humans. (The same chemotherapy drugs are used to treat both humans and canine lymphoma sufferers.) This form of cancer attacks lymphocytes and lymphoid tissue, which is typically found in bone marrow, the spleen, the liver, and the lymph nodes.


An aggressive form of cancer that frequently metastasizes to the lymph nodes and lungs, melanoma is also the most common type of oral cancer in dogs. 


While osteosarcoma — commonly called bone cancer — can impact any dog breed, it’s more common in large ones. Unfortunately, osteosarcoma is highly aggressive and painful as cancerous tumors begin to replace a dog’s bones. 

What does the start of cancer look like in dogs? 

Cancer has many forms, and not all types of cancer have drastic symptoms until it’s too late. We recommend regular cancer screenings if your dog is considered high-risk. Bernese mountain dogs, boxers, German shepherds, golden retrievers, and rottweilers all have an extremely high risk of developing cancer. With that being said, any breed can develop cancer at any age, so you should perform regular wellness checks at home. Here’s are the eight symptoms you should look out for. 

#1: Lumps under the skin

While some forms of cancer may leave visible lumps and bumps around your dog’s eyes, ears, nose, or mouth, not all cancerous tumors are visible to the naked eye. Try feeling for any abnormal swelling the next time you cuddle your dog. It could be nothing, but it could also be a tumor

#2: Sudden changes in urination and defecation 

If your pup suddenly begins to experience issues with urination and/or defecation, it could be a sign he has cancer. Fur babies suffering from urinary cancer may have to urinate more than usual, which could lead to accidents indoors.

A sad-eyed dog stands in a grassy field during sunset.

#3: Limping or lameness

Sometimes our fur babies over-exert themselves during playtime and feel sore the next day. But if your pooch experiences prolonged limping or lameness, it’s time to see a vet. Arthritis is a likely culprit, especially in senior dogs, but so is bone cancer. 

#4: Coughing, wheezing, or difficulty breathing

Just like humans, dogs are susceptible to cancerous lung tumors. Difficulty breathing, especially if your dog hasn’t been active, is always something that should be addressed by a veterinarian immediately. 

#5: Changes in food or water consumption

Cancer makes dogs feel unwell, which may impact their interest in food or water. Conversely, certain forms of cancer — specifically those with pituitary or adrenal gland tumors — may cause a sudden increase in food and water consumption. 

#6: Lethargy

While some pups enjoy lazing about all day, it’s cause for concern when a normally active dog suddenly displays symptoms of fatigue. It’s possible your pup is just having a sleepy day, but if your dog’s lethargy is accompanied by additional symptoms, it could be an emergency.

#7: Gastrointestinal distress

Although gastrointestinal issues aren’t what most people think of when they hear the word “cancer,” persistent or severe nausea, vomiting, and diarrhea are sometimes indicative of this disease. 

#8: Discharge from any orifice

A runny nose could be a symptom of a cold, but there’s also a chance your pooch has malignant nasal tumors. We always recommend taking your dog in for a checkup if he has unusual discharge from any orifice. 

How long can dogs live with cancer?

As much as we would love to give you a concrete answer, we can’t. The honest answer is: it depends. If a slow-spreading form of cancer is caught early, your beloved fur baby could live for several more years. However, if your dog has a highly aggressive form of cancer and is diagnosed when the disease is already in an advanced stage, then you may need to prepare for the worst in a matter of weeks. 

A closeup shot of a senior dog gazing up at the camera.

Pet parents, just like our furry family members, are all different. We have different jobs, different interests, and different lives. But we all have one thing in common: we wish our fur babies lived forever. Sadly, that’s not the case, but there are things you can do to make sure your beloved pup lives the best possible life. Keep a watchful eye on your dog’s health, take him to the vet for yearly checkups, and make sure your dog knows how much you love him. (No, really. They can tell if we truly love them.)

Editors' Recommendations

Mary Johnson
Mary Johnson is a writer and photographer from New Orleans, Louisiana. Her work has been published in PawTracks and…
6 summer bandanas for your dog to liven up the season in style
Will your dog go for the tropical palm tree bandana or prefer to stick to a muted solid?
Four Australian shepherd dogs sitting while wearing bandanas

You and your dog can rock out with just a simple accessory: bandanas for dogs. Because these only go around their necks like a collar, most pups don't mind, and it can even be fun for both of you. This summer, go all out by choosing a themed style for your animal (or take it another step further and match your outfits).
Hitting up the shore this summer? Your dog can look the part, too. Dress your pup up with a tropical-themed bandana for an easy way to get beach chic. This outfit can also be functional since you may want to protect them from the sun. Try out a slightly larger size and block a few rays.
If your little bud comes with you on vacation, get extra into your adventures by decking them out in the style of your destination. Perhaps you've decided to hit up "The Big Apple" and can dress them in an "I Love NY" bandana or you want to give them a Disney princess-themed scarf for a trip to sunny Florida.
Just in time for the Fourth of July, stock up on your America-inspired outfits. Flag code states that you should never wear the symbol but you can instead look for a red, white, and blue design. Alternatively, find other ways to celebrate the country by using patriotic images, such as national parks or historic monuments.

National Pet Month
The month of May is a time to celebrate pets. Take this opportunity to highlight your favorite cause like National Dog Mom Day (May 14) or National Rescue Dog Day (May 20). Another idea is to get your pet's name embroidered on a bandana of your choice to make it unique to them.
Instead of putting the spotlight on pets, try finding another animal to adorn your furry friend. They might look cute in a cat-themed bandana or perhaps one covered in unicorns. No matter what you decide, your fur baby will love being able to support their fave species (after dogs, of course).
Bandanas feature bright colors and patterns, but you can also stick with more muted pastels or neutrals to match your animal's coat. For example, a bright yellow could look especially boss on a black Lab for contrast or a beige might blend in nicely on a Shiba Inu. Don't forget to try rainbow and tie die, which is a reliable staple.

Read more
7 Japanese dog breeds that could be your perfect pet
Getting to know Japanese dog breeds: Shiba Inu, Akita, and more
A black and white Japanese Chin stands outside in the grass raising one paw

If you were to ask someone to name a Japanese dog breed, we'd be willing to bet that they'd mention Shiba Inu dogs first. And for a good reason! Shiba dogs are becoming increasingly popular around the world, especially after one lucky "doge" went viral in 2013. But they're not the only breed worth mentioning.
There are more than seven Japanese dog breeds out there, of course, but we chose these seven so you can compare and contrast these pups' unique qualities. From gentle giants to teacup cuties and everything in between, there just might be your perfect fit right here on this list!
Here are seven Japanese dog breeds we know and love.

Shiba Inu dogs are quite possibly the most famous Japanese breed, thanks to a meme
Whether you knew it at the time or not, you've probably seen a picture of the famous "doge" internet meme which features a Shiba Inu giving some major side-eye. And as it turns out, this infamous sass can be common in this self-assured breed!

Read more
Does your pet need to visit the dentist? Here’s how a dog teeth cleaning works
It seems scary but they won't feel or remember a thing
Doctor cleaning dog's teeth with toothbrush indoors

In theory, we all go to the dentist every six months to get our teeth cleaned, which helps keep the pearly whites in check and also contributes to overall health. Surprisingly, our pets also benefit from annual (or biennial) dental treatments. While these cleanings do wonders for your dog's teeth, they can make owners nervous and burn a hole in their wallets to boot. Here's why you should schedule regular cleanings for your pup.
How do I know if my dog's teeth need cleaning?
Unless it's a really severe case, you probably can't tell just by looking. Instead, your vet will take a peek in your animal's mouth during their yearly checkup. Your pet's doctor may give your furry friend a dental grade between 0 and 4, with 0 being reserved for puppies that have perfect teeth and 4 meaning Fido will likely require more advanced care, including extractions. Once you have the assessment, you can better determine if your pup needs a cleaning, but it's frequently recommended.
What happens during a dental cleaning
Some of that depends on the grade and your specific beast, but the gist of it stays the same. The main thing is not to worry too much because your little guy will be well cared for, and even though there's always some risk to anesthesia, this is a routine procedure.
Getting your pup ready
Before you even begin, you should get pre-op blood work done to make sure they can handle being under anesthesia. Have your vet discuss any outside-of-range findings and figure out the best way forward. Some older dogs develop kidney and liver problems, and your dog doc might decide that a cleaning isn't worth the risk.
Prepping for the cleaning
Your little guy will likely fast leading up to treatment (just as you would if you were going in for surgery). When you arrive, your vet will go over the schedule and almost certainly give them a once-over to confirm they're ready. Then they will get a sedative in preparation to go under. Figure out what time you need to pick them up and then try to distract yourself for a few hours.
During the procedure
Most vets will take X-rays, clean the teeth, and perform extractions as necessary. Don't worry — your pet will be fully asleep and will not remember or feel a thing. If they do need any teeth pulled, they might get additional shots during the visit (again, just as you would get Novocaine while getting your mouth done). Your vet may also take this opportunity to clip their nails (since they are asleep), if necessary.
If your dog had to have any work above a cleaning, you'll have a couple of meds to administer, such as pain medication and antibiotics. Follow the dosage carefully, especially if you're dealing with strong meds like codeine. In some circumstances, they may have to wear the cone of shame to prevent scratching at their mouth.
How else can you help your dog's oral hygiene?
There's a lot you can do as the pet parent in between cleanings. Consider brushing their teeth, giving doggie dental chews, putting an additive in their water, or putting them on prescription food if the issues are really severe.

The most important thing is to stay on top of your furry friend's oral health, just like you would with any other issues. That often means not feeding them human food, which can cause decay, and providing dry dog food or even dog bones to chew. As long as you stick with the routine, hopefully, you won't need too much extra detail care.

Read more