Lumps and Bumps on Dogs and Cats

Estimated Reading Time 4 minutes
Lumps and Bumps on Dogs and Cats

Could my pet have an infection? Allergic reaction? Splinter? Tumor? The answer is YES to all of the above or something else… In this article, we’ll touch briefly on some causes of lumps and bumps or abnormal growths in dogs and cats, what to look for, diagnosis, treatment, and when to call the vet.

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A lump or bump can appear anywhere on your pet, from nose to tail. Here we will be discussing abnormal growths that you may notice on the outside of their body such as the eyelids, tail, and between the toes.

What causes abnormal growths on dogs and cats?

Pets can get painful ingrown hairs, splinters, or other foreign objects stuck in their paw or skin that result in swelling, inflammation, pain, and sometimes infection.

Insects such as fleas, ticks, and mosquitoes also bite our pets, causing a localized allergic reaction.

Often, senior pets develop lumps and bumps that turn out to be benign while others can be malignant cancer. Benign cancer means that the tumor doesn’t spread to other parts of the body. Malignant cancer often spreads to lymph nodes as well as body organs such as the lungs, brain, skin, liver, and kidneys.

Other causes of abnormal growths on dogs and cats include:

  • Infected anal glands
  • Abscessed or infected tooth
  • Abscess or infection due to dog fight or cat fight
  • Hematoma (a fluid-filled area of blood without infection, usually caused by trauma)
  • Lipoma (a benign fatty tumor)
  • Mammary tumor (may be benign or malignant)
  • Testicular tumor
  • Eyelid tumor
  • Glaucoma (enlarged eye caused by increased pressure within the eyeball)

What should I do if I find a lump on my dog?

Not knowing if a growth is due to infection, inflammation or tumor often causes pet parents unnecessary worry. Knowing what’s causing the swelling can help calm your worst fears.

If you notice a lump or bump, contact your vet. They will be able to determine the cause and appropriate treatment if needed. Sometimes when caught early, malignant cancer can be treated, allowing your pet good quality time with minimal to no discomfort.

  • While you spend time with your pet, you can check them regularly for any new lumps, swellings, or growths:
  • Groom your pet often by brushing and petting them. Take note of any abnormal lumps or bumps.
  • Check their eyes, ears, mouth, and under the tail, while rubbing their belly and trimming or checking their nails.
  • If your male dog is not castrated, check his testicles to make sure they are similar in size and shape.
  • If you notice a lump or bump, gently check for redness, pain, and discharge.

What will the vet do to check my dog’s lump?

Veterinarians can’t tell if a growth is abnormal simply by looking or examining it. Tests such as a Fine Needle Aspirate (FNA), biopsy, or surgery may be necessary to figure out the diagnosis. Bloodwork, urinalysis, x-rays, and ultrasound may be needed, especially if a growth is malignant.

How are lumps and bumps treated?

Treatment depends on if the abnormal growth is due to infection, inflammation, a foreign object, or cancer.

If the problem is fleas and ticks, your vet can talk to you about flea and tick prevention and control. Click on the following links to learn about controlling fleas and ticks on your pets:

Tick Talk - Small Animals and Tick Control

How to Safely Manage Fleas in Pets

Growths due to infections often need antibiotics and pain medications. If the infection is due to an abscessed tooth, the tooth will need to be treated or extracted under general anesthesia.

Cat and dog fights where the skin is broken by biting and scratching often result in an abscess that needs to be surgically drained under anesthesia. Cat and dog fight wounds and abscesses require antibiotics and pain medications to be continued at home.

Pets diagnosed with benign tumors such as lipomas may simply need to be monitored for increasing size as they can cause problems depending on the location (such as under the armpit). Your vet may recommend surgical removal if the tumor is growing. Benign tumors located on the bottom part of the leg often need to be removed because there is very little skin. This can make surgical removal difficult if the tumor gets larger.

Pets diagnosed with malignant tumors often need surgery under anesthesia. They may also need additional treatments such as chemotherapy. Small malignant tumors that are noticed early and haven’t yet spread to other organs can be surgically removed.

Read more:

Mast Cell Tumors in Dogs

Cancer (Neoplasia) in Cats

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