Lipomas in Dogs: Symptoms, Causes and Treatment

What is a Lipoma?

A lipoma is a benign fatty lump located between a dog’s skin and muscle layer. They form from fat cells that clump together in a capsule in the subcutaneous tissue. Lipomas feel soft, squishy, and movable when handled.

They are not cancerous and usually cause no problems other than being unsightly. However, lipomas can occasionally impinge on surrounding structures, such as joints or nerves, if they grow large enough.

Common Locations

Lipomas most often occur on the torso in areas with looser skin and fat. Common locations include:

• Chest
• Abdomen
• Upper legs
• Armpits

They also frequently develop on the neck, shoulders, and back. Lipomas tend to form in middle to older aged dogs, especially those who are overweight.

Appearance

Lipomas are typically round or oval shaped lumps that protrude from the skin. They have well-defined margins with a smooth surface. The skin covering them may feel warmer compared to surrounding areas.

In dogs with thicker fur, the lump itself may be hidden. But it can be felt with palpation, sliding freely under the skin. Lipomas range from pea-sized to several inches wide in some cases.

Soft vs. Firm

Most lipomas have a uniform soft, mushy consistency. But some develop calcifications or fibrous tissue over time that makes them feel firmer.

These mineral deposits cause the lipoma to feel harder and irregular compared to the typical homogeneous fatty mass.

Symptoms of Lipomas in Dogs

In many cases, a lipoma is found incidentally while petting or brushing your dog. They usually develop slowly and cause no signs unless they compress on tissues due to their growth.

Possible symptoms include:

• Visible lump under or protruding from the skin
• Loss of fur over the lipoma
• Enlarging or changing lump
• Seeming uncomfortable or lame when lump is touched
• Difficulty moving or reduced range of motion
• Pain when nearby area is touched or manipulated

Signs like lameness or discomfort are more common when lipomas grow in joint areas like the armpits, groin, or behind the knee. Nerve compression can cause pain or muscle weakness as well.

Appears Over Time

In most cases, a lipoma starts small and enlarges slowly over weeks to months. Dogs often develop additional lipomas over time. Your vet can compare current lumps to previous exams to determine if they are new growths.

Does Not Usually Cause Pain

Lipomas are typically painless. Even large lipomas generally don’t cause discomfort unless they impinge on other structures. Sudden pain or tenderness associated with a lipoma may indicate complications.

Moves Under the Skin

The lipoma can be moved freely beneath the skin with gentle manipulation. Pinching and sliding the lump across underlying tissues helps distinguish it from growths fixed to deeper structures.

Causes of Lipomas in Dogs

The cause of most lipomas is unknown. There are no proven risk factors. However, possible contributing factors include:

Age

Lipomas usually develop in middle-aged to older dogs, typically first appearing between ages 6-10. Risk seems to increase with age as the body’s metabolism changes.

Obesity

Overweight and obese dogs have a higher chance of developing lipomas compared to dogs fed a healthy diet and ideal body weight. Excess body fat predisposes to lipoma formation.

Genetics

Certain dog breeds are more prone to lipomas, suggesting a possible genetic link. At-risk breeds include Dobermans, Labrador Retrievers, Schnauzers, and mixed breeds.

Trauma

Injury to the skin may trigger the development of a lipoma in some cases. However, most form spontaneously without any trauma to the area.

Diagnosing Lipomas in Dogs

Lipomas are usually diagnosed based on appearance and feel during a physical exam. However, additional tests may be recommended to confirm the diagnosis and rule out cancer.

Physical Exam

Your vet will palpate the lump, feeling for its texture, mobility, and relationship to surrounding tissues. Features that suggest a lipoma include:

• Soft, squishy feel
• Moves freely under skin
• Lack of pain
• Homogeneous texture
• Non-fluctuant
• Smooth margins

Your vet may move and manipulate the mass more to assess its mobility and whether it seems fixed to any structures.

Fine Needle Aspiration

This test uses a small needle to extract cells from the lump for examination under a microscope. It can help identify fat cells typical of a lipoma.

Biopsy

Surgery to remove and biopsy the entire lump may be recommended. This is the only way to definitively diagnose a lipoma and rule out cancer.

Imaging

X-rays, CT scans, or MRI may be used to evaluate the size, shape, and location of a lipoma. This is more common if it is compressing other structures.

Lipoma Treatment in Dogs

Treatment usually isn’t necessary for most lipomas. However, options include:

Monitoring

Small, asymptomatic lipomas can simply be monitored at home. Check for any changes in size, shape, firmness, or pain at least monthly.

Weight Loss

Helping an overweight dog slim down may help shrink or prevent new lipomas from forming.

Lipoma Injection

A steroid may be injected into the lipoma to promote shrinkage. However, results are often temporary.

Surgery

Surgical removal is an option for large or problematic lipomas. Tumors causing lameness, nerve issues, or suspicion of cancer are common reasons for excision.

Preventing Lipomas in Dogs

There is no way to fully prevent lipomas. But the following measures may help lower risk:

• Feeding a healthy weight control diet
• Avoiding obesity
• Exercising regularly
• Keeping fatty skin folds clean
• Monitoring lumps routinely
• Early veterinary diagnosis

Catching lipomas early makes them easier to manage. Routine exams and alertness to new lumps is important, especially in prone breeds.

When to See the Vet

Make an appointment with your vet if your dog develops a new lump or bump anywhere on the body. Recommendations include:

• Have all new lumps examined
• Monitor existing lipomas for any changes
• Return sooner if a lump seems painful, bleeds, ulcerates, or impedes movement
• See the vet promptly for lameness, weakness, or unusual swelling
• Biopsy rapidly growing or very firm masses

Though most lumps are harmless lipomas, examination helps ensure serious issues like cancer are diagnosed early when treatment is most effective.

Lipoma Pictures in Dogs

Here are some photos of typical lipoma appearance in dogs:

The Bottom Line

Lipomas are extremely common, harmless fat lumps in older dogs. Monitoring at home is often sufficient treatment. But have all new lumps examined promptly since some require biopsy or removal, especially fast-growing masses.

Catching lipomas early, maintaining your dog’s ideal weight, and inspecting their skin during routine handling can help optimize their health and longevity.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.