Epulis Tumors in the Mouths of Dogs

epulis tumors may show up in the mouth of dogs like this one

Kelly Serfas, a Certified Veterinary Technician in Bethlehem, PA, contributed to this article.

Tumors in the mouth or on the gum are sometimes tough to discover early on. They can hide in difficult-to-see locations. Sometimes, they are visible near the front teeth or right under the lip. They are typically discovered during a thorough physical exam or during a dental cleaning.

Epulis Tumors and dogs
One of the most common types of oral masses is called an epulis (pronounced eh-pew-liss). This mass can mean many different things to different people. Most of the time, an epulis is considered benign. However, below the surface of the mass, something much more threatening may be lurking.

An epulis is a firm, pinkish and irregular growth found on the gum of middle-aged dogs (about 8 years of age on average). The growth can rarely occur in cats too. As long as the mass is small, there are few clinical signs. It can occur in any dog breed, but most commonly in brachycephalic breeds, i.e., breeds with a flat face, such as boxers. Unfortunately, boxers are also at risk for a benign condition called gingival hyperplasia, which means that the gum has a bunch of exuberant, but benign, growths. The two conditions can look the same, and can even occur at the same time!

With an epulis, you may notice bad breath (halitosis), drooling or bleeding from the mouth. As the mass becomes larger, your dog may have trouble eating. A visit to the vet may reveal a mass along the gum.

It’s not “just an epulis”
At that point, please don’t let anybody ever tell you “it’s just an epulis,” as this could be a huge disservice to you and your dog. It would be the same as saying “it’s just a tumor.” We need to know more in order to make the right decision. And the sooner that is, the better for your dog.

An epulis can be benign (i.e. non-cancerous) or malignant (cancerous). But it’s a little bit more complicated than that. Even a benign epulis can cause a lot of trouble. This type of tumor can be “locally invasive,” which means that it can grow into the jaw bone and literally eat the bone away. Even though it doesn’t spread or metastasize to other organs, it is considered aggresive.

Diagnosing and treating an epulis
The only way to know which type of epulis we are dealing with, is to take a biopsy and send it to the lab for analysis. While the dog is under sedation or anesthesia, jaw X-rays should be taken to see if the bone has been eaten away by the tumor.

If the epulis is benign (fibromatous or ossifying type), it can be removed – generously, so that we decrease the chances of the mass coming back.

If the epulis is malignant (acanthomatous type), surgery must be much more invasive, which means that you may be referred to a veterinary surgeon or dentist. Because the bone is involved, part of the jaw (upper or lower) needs to be sacrificed. While this may sound terrible, dogs typically do very well after surgery. It is not unusual for them to eat the evening of the surgery or the next morning!

You will have to offer soft food for a few weeks. Once the incision has healed and the fur grows back, most dogs look fairly normal.

Occasionally, an acanthomatous epulis is treated with radiation therapy or chemotherapy.

Once we know what we are dealing with, we know how to treat an epulis. The difficulty is to diagnose it early.

Questions to ask your veterinarian

  • Why does my dog have bad breath or why is my dog drooling?
  • If a mass is found: what can we do to reach a diagnosis?
  • Who is the best person to remove it?

If you have any questions or concerns, you should always visit or call your veterinarian -- they are your best resource to ensure the health and well-being of your pets.

Related symptoms: 
Reviewed on: 
Friday, October 28, 2016