Common Lumps and Bumps on Pets

What to Watch for and When to Worry

Veterinarian doing a check-up on a Corgi in clinic

Ron Levine/Getty Images

Finding a lump on your pet can be scary. All lumps should be checked by a veterinarian, especially if your pet acts lethargic, seems to be in pain, has a drastic change in habits, or keeps licking or rubbing the lump. Your vet will assess the location, size, firmness, duration, and may use a needle to aspirate the lump and examine the cells under a microscope. This collection of "lumps and bumps" resources and photos answers some common questions about lumps in dogs and cats.

  • 01 of 05

    Pedunculated Polyp or Tumor

    Dog in a vet's office

    Steven G. Smith/EyeEm/Getty Images

    When used with the words polyp or tumor, pedunculated means a growth on a small stalk. This can be anything from a small skin tag to a larger growth anywhere on the body. These usually benign lumps can often be easily removed. However, there are some can cause problems for your pet. There are some types of pedunculated polyps or tumors that can grow inside the body. They run the risk of becoming strangulated (or twisted) and cut off from the blood supply of the body. This can cause cellular death, internal infections, and other problems within your pet's body. Your vet can diagnose any pedunculated polyp or tumor, and can usually determine the type with an in-office examination.

  • 02 of 05


    Histiocytoma on pink skin

    Lianne McLeod/The Spruce

    A histiocytoma is a benign skin tumor usually seen on younger dogs, often three years old or under. This type of skin tumor has a bright red button-like appearance and can appear overnight. On most dogs, they are most often found on the head, neck, ears, and limbs (however, they can be present in other places). Histiocytomas tend to be less than 2.5 cm in diameter. They rarely cause pain and often spontaneously disappear without treatment. Based on the location of the histiocytoma, a dog may not even be aware of the tumor. It is important to prevent your dog from rubbing, licking, scratching, or biting the tumor. This will help prevent inflammation, infection, and bleeding. If you notice one on your dog, take note (and photos) of its location, size, and color. Share this information with your vet to let them decide the course of action.

  • 03 of 05

    Lipomas (Fatty Tumors)

    Lipoma on dog's neck prepped for surgical removal

    Photo from Janet Tobiassen Crosby DVM

    Fatty tumors called lipomas are one of the most common types of lumps found on pets, especially older dogs and overweight females. Additionally, certain dog breeds may be especially prone to developing lipomas, including Doberman Pinschers, Schnauzers (miniatures), Labrador Retrievers, and mixed breeds. They can also appear in cats and horses, but not as often as dogs.

    Usually, lipomas are found just under the skin, but they can be locally invasive, meaning they have grown together with muscle or connective tissue. Most vets will perform a needle aspiration to determine and confirm that the lump is a lipoma. Once confirmed, many will adhere to a "watch and wait" approach to treatment. The vet will continue to check the lipoma at regular intervals and decide if it needs to be removed. If it is a particularly large lump, especially if it is located under a limb or in another location that will interfere with movement or function, the vet will likely choose to remove it as quickly as possible, via surgery.

  • 04 of 05

    Lipoma Removal on a Dog

    Lipoma removal surgery

    Photo from Janet Tobiassen Crosby DVM

    This surgical step-by-step shows the removal of a lipoma. Please note: The graphic photos in this gallery may not be appropriate for those who feel squeamish at the sight of blood or surgery.

    Continue to 5 of 5 below.
  • 05 of 05

    Tips for a Productive Vet Visit

    If you are taking your pet to the vet for a suspicious lump or bump, it's best to be prepared ahead of time to have a productive vet visit. Your vet will likely want to know:

    • When the lump was first noticed or if the lump seemed to appear suddenly
    • The initial shape, color, and size, and if any of these details have changed since the first discovery
    • Any significant changes to your animal's behavior, appetite, or energy recently (or upon noticing the bump)

    When you first discover a lump or bump, it can be helpful to take a picture (with a ruler or other measurement reference point like a fingertip). This will allow you to share the photo with the vet and easily monitor if and how the size and shape have changed.

Please note: This article has been provided for informational purposes only. If your pet shows any sign of illness, please consult a veterinarian as quickly as possible.

If you suspect your pet is sick, call your vet immediately. For health-related questions, always consult your veterinarian, as they have examined your pet, know the pet's health history, and can make the best recommendations for your pet.