Lipomas in Dogs & Cats: Causes, Diagnosis & Treatment of Fatty Tumors

Pet Lipomas: fatty tumor causes, diagnosis & treatment

Finding a lump on your fur-baby can be scary. Is it a bug bite? An injury? Or worse, is it a cancerous tumor?

It could be a lipoma -- totally benign (non-cancerous) and totally treatable.

In fact, I had one a few years ago. A big old lump on the back of my shoulder. It started out small and grew over time. Eventually it was getting large enough to see through my shirts, so I decided it was time to see my doc.

Fortunately, it was nothing more than a lipoma. A fatty tumor. One quick surgery and just like that, it was gone.

But lipomas aren’t exclusive to humans. Our pets can get them, too. 

Our little pug, Abby, had one on her leg. We didn’t see any reason to have it removed since she didn’t seem bothered by it in the slightest. 

That was just our personal experience, though, and there’s no right or wrong answer on how you should respond to your pet’s lipoma. First thing’s first: get the facts.

Here’s what you need to know about your pet’s lipoma ...

What is a lipoma?

Lipomas are fatty tumors. 

OK, but what exactly is a tumor? A tumor is an abnormal growth of cells. They can be benign (non-cancerous) or malignant (cancerous).

RELATED POST: Mast Cell Tumors (MCT): Symptoms, Diagnosis, Treatment

Lipomas (fatty tumors) are not the scary malignant (cancerous) kind of tumors. They’re just plain old overgrown chunks of fatty tissue. 

Every year, roughly 1.7 million dogs in the United States are treated for lipomas. They are far less common in cats, although older, male, neutered Siamese cats are at a higher risk of developing lipomas.

What causes lipomas in pets?

No one really knows what causes dogs, cats or even humans to develop a lipoma. Some say they can be caused by diet. Others blame chlorine in the tap water. And contrary to popular belief, lipomas are not a result of obesity.

According to VCA Hospitals, “Most seem to be caused by a complex mix of risk factors, some environmental and some genetic or hereditary.”

Breeds more predisposed to fatty tumors include: 

  • Labrador Retrievers
  • Dobermans
  • Shetland sheepdogs
  • Dachshunds
  • German Pointers
  • Weimaraners
  • Miniature schnauzers
  • Springer Spaniels

That’s not an exclusive list, mind you. Any breed of dog (or cat) can develop a lipoma. We believe the best way to keep your pets healthy is from the inside.

Here are some of the supplements your fellow pet parents trust:

How to diagnose pet lipomas

Lipomas feel soft to the touch and they can show up just about anywhere on the body. They’re typically round or oval, and they come in all sizes. Fatty tumors feel, you guessed it, like a ball of fat. They tend to move freely and have well-defined edges.

Your vet will first do a fine needle aspiration (FNA) to collect a tissue sample from the lump then look under a microscope to see what it is. In less common instances where FNA results aren’t conclusive, your vet may have to do a biopsy to rule out other causes of the bump.

How to treat pet lipomas

Since they generally don’t pose a threat to your pet’s health, it’s up to you as a pet parent to decide if you want to have it removed. If it’s not affecting your pet’s mobility, there may be no reason to have it removed.

On the other hand, if it continues to grow, causing your pet to scratch, lick or bite the area, then it might be time to think about surgery.

Before surgery, your vet will perform some tests to make sure your fur-baby is healthy enough to handle the procedure. Some of those test might include:

  • Bloodwork to evaluate:
    • kidney, liver and pancreatic function
    • if your pet has been exposed to infectious disease
    • and rule out blood-related conditions

Your vet may also perform:

  • A thyroid test (looking for normal hormone levels) 
  • An electrolyte test (looking for an electrolyte imbalance or signs of dehydration)
  • A urine test (to rule out urinary tract infection and to evaluate kidneys’ ability to concentrate urine)
  • An electrocardiogram (looking for an abnormal heart rhythm possibly caused by heart disease)

Can I prevent my pet from getting a lipoma?

Probably not. Since we don’t really know exactly what causes these fatty tumors to grow, there isn’t anything you can do to prevent them. For some pets, they’re just a natural part of aging. For others, it’s a hereditary condition. 

If you find a tumor on your dog or cat, the most important thing you can do is schedule an appointment with your vet. While most lumps and bumps are nothing to worry about, it’s better to be safe than sorry. Act quickly to rule out a potentially dangerous condition. Then talk to your vet about the best way to treat (or not treat) your pet’s lipoma.