Skip to main content
  1. Home
  2. Dogs

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

Mary Johnson
By

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.
Image used with permission by copyright holder

What is the most common cancer in dogs? 

According to cancer.gov, 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:

Recommended Videos

Hemangiosarcoma

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.

Lymphoma

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.

Melanoma

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. 

Osteosarcoma

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.
Image used with permission by copyright holder

#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.
Image used with permission by copyright holder

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

Topics
Mary Johnson
Mary Johnson
Contributor
Mary Johnson is a writer and photographer from New Orleans, Louisiana. Her work has been published in PawTracks and…
What to do if your dog keeps throwing up with no sign of stopping
Here's what to try first and when to call the vet
A dog sleeping in a bed with a water bottle on his head and a thermometer in his mouth.

If you're like most pet parents, the sight of your beloved dog throwing up sends shivers of fear down your spine. Just like us, dogs occasionally eat something that disagrees with them and causes them to vomit. In most cases, your dog's vomiting will resolve on its own, but if your pup keeps throwing up, it could be cause for concern.

We'll give you the rundown on everything you need to know about why your dog keeps throwing up, from potential reasons why your pet might be vomiting to when you should take your pooch to the vet. 

Read more
Can dogs eat celery? The do’s and don’ts you should know
Your pup will probably love a veggie snack now and then
Woman chops up veggies including celery for her dog

Your dog's favorite snacks might include dog biscuits, fancy chews, or even that bacon you dropped on the floor one time, but can dogs eat celery? The truth is lots of dogs like veggies, even bland ones such as celery. While you wouldn't want this green and healthy nibble to become a staple in their diet, you can absolutely give your pup a celery snack now and then — and they might grow to love it.

Can dogs have raw celery?
As omnivores, our pet dogs need a balanced diet of both meat and plants. That's likely because their domestic history made them into scavengers thousands of years ago when our ancestors were still in the hunter-gatherer phase. In modern times, this diet preference has huge benefits because you can throw in some healthful treats that will give your pup a nutrition boost and keep them full.

Read more
Seizures in dogs can be scary – this is what you need to do
How to help your dog if they have a seizure
Australian shepherd by brick wall

Witnessing a seizure can be jarring, especially if you never have before. You may feel scared and helpless if the person is a stranger at a restaurant or a friend or family member. What if that friend or family member is of the furry variety? The experience can take on new layers — you're supposed to care for and help a dog, but you have no idea what to do.

Your best bet is to call the vet if your dog has never had a seizure. Should the veterinarian's office be closed, an emergency hospital is equipped to handle seizures in dogs. If your dog is prone to seizures, your vet likely gave you instructions on what to do — follow them. However, perhaps you're in the lobby waiting for answers, trying to make sense of what happened. Alternatively, maybe you're a pet parent-to-be who wants to be prepared for anything and everything. This guide to seizures in dogs can help.

Read more