Lumps & Bumps in Dogs: When Should I Be Concerned? (2023)

Finding a new lump in a dog can often lead the owner to spiral out of control. Some lumps are benign and expected as the dog proceeds into old age. But other lumps are cancerous and, in this case, it’s only right to be concerned. How do you know when you should be worried about your dog’s lumps and bumps?

The bottom line is that all lumps and bumps deserve our attention because staying on top of your dog’s health is always good. Therefore, this article comprehensively discusses lumps and bumps so that you can feel a bit more at ease and capable of dealing with these nasty growths.

What to Do When You Find a Lump:

One of the most important factors to know is the cause of the lump. Some of the causes can give you a good idea of whether you should be concerned and the treatment will depend on the specific cause. So, let’s look at some of the common causes of lumps and bumps in dogs:

Excess Fat

In overweight and older dogs, fat deposits under the skin sometimes form lumps and bumps. These lumps are benign though they may be removed if they interfere with the dog’s movements.

A preventative measure you can take to avoid your lumps and bumps from excess weight is to provide a balanced diet

(Video) Dr. Danielle Spencer explains what bumps and lumps on your dog could mean

Canine Abscess

Abscesses present as firm or fluid-filled lumps that have variable shapes and sizes. Pus accumulates in these lumps. The cause may be an infection but other factors such as injuries are also common with abscesses. If it is an infection, then the dog will also show other symptoms such as fever and a loss of appetite.

Acral Lick Dermatitis

Sometimes, dogs will develop an obsessive habit of licking themselves to such a point that they cause trauma or lesions on the skin. This is often brought on by stress, anxiety, or boredom. The lesions that result tend to red, well-rounded, and raised bumps. Controlling the underlying issues such as anxiety or stress is often the solution. Fitting an Elizabethan collar on the dog also helps to manage the obsessive behavior.

Cancer in Dogs

Several forms of canine cancer present with lumps as symptoms. This includes lymphoma, mammary cancer, mast cell tumor, and melanoma. Lymphoma presents as an itching, red, and ulcerous lymph. Mammary cancer is common in unsprayed females and about 50% tends to be benign. Mast cell tumor appears in various sizes, amounts, and appearances, and it is usually graded from stage 1 to stage 4, depending on its severity. Lastly, melanoma appears as a single, dark-colored bump that usually ulcerates (appearing like an open sore).

Whatever form of cancer may be underlying the lump, a biopsy and/or other medical examinations are very important. Quick and easy cancer detection tips such as whether a cancerous lump tends to be hard or soft will not cut it – mast cell tumor, for instance, comes in varying appearances (hard or soft, big or small). So, it’s good to consult your vet as soon as you find the lump.

(Video) Is this Lump Serious? 5 Steps to Know

What You Need to Know about Your Dog’s Lumps and Bumps

It’s not always easy to pin down the exact cause of the lumps on your dog. Therefore, it’s better to consult your vet for a proper check-up and examination of the lump(s). Some of the things your vet will want to know are;

  1. Whether the lump suddenly appeared or if it developed gradually over time.
  2. Whether the size, shape, or color of the lump has changed over time.
  3. Whether there are other symptoms you have noted for your dog, such as a loss of appetite.
  4. Medical history of your dog, especially if he or she has experienced lumps and bumps in the past.

Tip: While looking forward to the above questions in your vet visit, it can be helpful to provide a picture of the lump or bump when it first appeared, along with a ruler or some other manner of measurement (someplace a quarter beside the lump or bump). It’s also good to show the location of the lump in those images. Progressive ‘evidence’ of this kind can inform the vet more than anecdotal accounts.

The Most Common Types of Lumps and Bumps in Dogs

Some of these lumps may seem familiar, especially after going over the causes of lumps above;


These are also known as fatty lumps; they appear as soft, rounded masses just under the skin and they are not painful.

They are the most common type of lumps you’ll encounter and are more prevalent in elderly and overweight dogs. Most lipomas are harmless or benign but some may be removed if they are irritating for the dog.

(Video) 🐶LUMPS on DOGS and When You Should Be Concerned

Mast Cell Tumor

This is another common type of lump in dogs. Breeds such as Boxers, Boston terriers, Labradors, schnauzers, and beagles are more prone to developing mast cell tumors. Mast cell tumor is a form of skin cancer and can become malignant if not checked. As mentioned above, mast cell tumors come in varying shapes, sizes, and appearances.

Sebaceous Cyst

These are usually non-cancerous, harmless bumps on the skin caused by plugged oil glands, dead cells, or sweat. Eventually, these bumps will rapture and the skin heals properly. If the sebaceous cyst becomes severely irritated or infected, though, it may require removal. In these cases, a pathologist may examine the cyst to ensure that it was not something more serious.

Sebaceous cysts are more common with breeds such as Cocker Spaniels, schnauzers, Yorkies, and poodles, but any dog can develop sebaceous cysts.


Warts appear as small skin tags or as a series of small lumps on the head and face. They are more common in elderly dogs, puppies, or in dogs that have a compromised immune system. Warts are caused by canine papillomavirus and may be transmitted from one dog to another through social contact. The good news is that warts are benign and they usually go away after a short while. However, they may irritate your dog a great deal and, in that case, it may be good to look into removing warts.


This is another form of skin cancer that we touched on above in the causes of lumps discussion. Certain cases of melanoma are benign especially if their cause is not associated with harm from sun rays – these can be treated through surgery. Severe forms of melanoma may metastasize into the mouth, legs, and other organs of the body. Therefore, it’s important to consult your vet as soon as you notice an ulcerated lump or a dark-colored lump on your dog.

(Video) Tumors, lumps, and bumps When should you be concerned


These lumps appear as red, round umps, or a series of round or oval, raised bumps on his or her skin. Hives itch a lot. The cause of a hive could be an allergen such as a harmful substance from a plant that your dog made contact with, a bee sting, or some other allergen. Hives usually go away on their own but due to the itching discomfort your dog may feel, a vet may provide an antihistamine to hasten that healing.

When You Should Be Concerned

Lumps that appear in these ways deserve to be handled as soon as possible:

  1. Lumps that grow at a rapid pace over a month or a few weeks.
  2. Lumps that are painful when touched or when a part of the dog body makes contact with the lump, for instance in an armpit when moving about.
  3. Lumps that ooze a discharge or a lump that discolors the skin in that region. In this case, it is likely an infection is the underlying problem and it needs to be addressed immediately.
  4. Lumps and bumps that grow and then shrink again. Mast cell tumor has bumps that appear in this fashion because of the repeated discharge of histamine (that substance that causes swelling in allergies). Scratching or poking these bumps may cause even more histamine to be released. So, it’s best to address it quickly before they can grow large due to the dog scratching or poking the bumps.
  5. Bumps or lumps that grow in size in a matter of minutes. This is often a sign of an allergic reaction and immediate treatment is recommended.

Final Thoughts

Noticing a new lump on your dog’s skin can be a scary thing. But it doesn’t have to be this big anxiety-inducing experience if you have all the information about lumps in dogs.

One of the best snippets of wisdom you’ll get as a dog owner is that you should regularly monitor your dog’s body. Often, dogs can develop health issues and not give a whiff to notify you until the problem has progressed too much. Therefore, it’s wise to keep yourself apprised of what is normal in your dog’s body and what is abnormal. Run your fingers over his or her coat to check for lumps and bumps. This regular exam will also come in handy when the Vet asks such questions as whether the lump appeared suddenly.

(Video) Is it Cancer? Pet Lumps & Bumps - VetVid Episode 023

Related Articles:

  • The 12 Lumps (and Bumps) of Canine Skin
  • How to Know If Your Limping Dog Needs to See a Vet
  • 3 Common Health Issues as Dogs Get Older
  • Why Is My Dog Limping?
  • 5 Common Skin Issues in Old Dogs and How to Manage Them

Did we answer all your questions on "Lumps & Bumps"?


How do I know if my dog's lump is serious? ›

Unless you're sure about the cause of a lump or bump, bring your dog in for an exam. If you see fast growth, redness, swelling, pus, an opening, or if the dog is in pain, make that appointment even sooner.

What do cancerous bumps feel like on dogs? ›

One of the best ways to identify a potentially cancerous lump is to evaluate how that tumor feels when touched. Compared to the soft, fatty characteristics of a lipoma, a cancerous lump will be harder and firm to the touch, appearing as a hard immovable lump on your dog.

When should I take my dog to the vet for bumps? ›

If you've found a lump or bump on your pet, give us a call right away to make an appointment. Because the difference between a benign mass and something more serious isn't always obvious, your veterinarian needs to take a look.

Why does my dog have so many lumps and bumps? ›

Lipomas (fatty lumps)

Lipomas are the most common benign mass dogs can get; they're often found under the skin of older dogs, and are more common in obese dogs. They tend to be round, soft tumours of fat cells that grow very slowly and rarely spread, so it can take up to six months before you see any change.

What does a cancerous lump look like? ›

Bumps that are cancerous are typically large, hard, painless to the touch and appear spontaneously. The mass will grow in size steadily over the weeks and months. Cancerous lumps that can be felt from the outside of your body can appear in the breast, testicle, or neck, but also in the arms and legs.

How do you tell if a growth on a dog is cancerous? ›

Symptoms And Signs Of Cancer In Dogs
  1. Lumps and bumps underneath a dog's skin.
  2. Abnormal odors emanating from the mouth, ears, or any other part of the body.
  3. Abnormal discharge from the eyes, mouth, ears, or rectum.
  4. Abdominal swelling.
  5. Non-healing wounds or sores.
  6. Sudden and irreversible weight loss.
  7. Change in appetite.

Can a vet tell if a lump is cancerous? ›

The only definitive way to determine if a mass is cancerous or benign is to have it examined by a veterinarian. If you find a new mass on our pet, please have you veterinarian evaluate it. To do so, your vet may perform a test called a fine needle aspirate.

What kind of lumps are normal in dogs? ›

Lipoma. The most common benign lump that dogs develop, a lipoma is a fat-filled tumor found under the skin of middle-aged or older dogs and is considered a natural part of aging. These soft, rounded, non-painful masses grow slowly and rarely spread.

What Colour are cancerous lumps on dogs? ›

Malignant melanomas are another type of skin tumor of older dogs. They commonly develop on the lips, mouth, and nail beds of male dogs. They appear as raised, ulcerated lumps and may be dark, light gray, or pink. If they appear in the nail bed, the toe is often swollen.

What percentage of bumps on dogs are cancerous? ›

Of submitted samples, 20% to 40% are reported to be malignant. The most common malignant skin tumors in dogs are mast cell tumors, soft tissue sarcomas, and squamous cell carcinomas. The most common benign canine skin and subcutaneous benign tumors include lipomas, histiocytomas, and perianal gland adenomas.

How do you tell if my dog has a cyst or tumor? ›

Dog Cyst vs Tumor: How Do I Tell The Difference? Cysts are fluid-filled sacs under the skin that are usually easy to move around, while tumors are typically more solid. A cyst also may drain a white, yellow, or green discharge.

Why is my dog suddenly getting lumps all over his body? ›

Most lumps that develop on dogs are benign, which means non-cancerous. These lumps can actually be fat, fatty tumors, cysts, warts, abscesses, or multiple other alternatives. Fatty tumors are common in older dogs and can cause sudden lumps on your pup.

Why does my dog suddenly have lumps all over? ›

Some common causes of lumps and bumps on dogs are: Inflammation or swelling that's usually in response to an insect bite or bacteria. An abscess, or a painful accumulation of pus caused by bacteria. Allergic reactions that look like hives.

What age do dogs get fatty lumps? ›

As dogs age, their odds of getting lipoma increase. Dogs aged between 9-12 years were over 17 more likely to be diagnosed with lipoma compared to dogs aged 3-6 years old. Neutered dogs had higher risk. Insured dogs had 1.78 times the odds of diagnosis.

How do you know if a lump is a concern? ›

See a GP if:
  1. your lump gets bigger.
  2. your lump is painful, red or hot.
  3. your lump is hard and does not move.
  4. your lump lasts more than 2 weeks.
  5. a lump grows back after it's been removed.
  6. you have a lump in the breast or testicles.
  7. you have a swelling on the side of your neck, armpit or groin that does not go down.

How can you tell if a lump is harmless? ›

A lump that grows and then goes away on its own can usually be attributed to an inflamed cyst, which is normally harmless. A “doughy” lump is usually associated with a benign lipoma. Likewise, lumps that are harmless can often be accompanied by tenderness, pain, or drainage.

How big are cancerous lumps usually? ›

Breast cancer lumps can vary in size. Typically, a lump has to be about one centimeter (about the size of a large lima bean) before a person can feel it; however, it depends on where the lump arises in the breast, how big the breast is, and how deep the lesion is.

How quickly do cancerous lumps grow on dogs? ›

While some may be present for many months without growing much, others can appear suddenly and grow very quickly. Sometimes they can suddenly grow quickly after months of no change. They may appear to fluctuate in size, getting larger or smaller even on a daily basis.

Do cancerous lumps appear suddenly on dogs? ›

They often appear overnight and sometimes will disappear without treatment. Some dogs may chew or bump these masses and make them bleed. If the tumor does not resolve itself or is bothering your pet, surgical removal may be recommended after speaking with your veterinarian.

Are cancerous tumors on dogs hard or soft? ›

Cancerous or malignant tumors can be hard or soft. The feel of a mass and whether it bothers your dog has little to do with whether it is cancerous or not.

What do fatty tumors look like on dogs? ›

A lipoma will typically present initially as a small, hemispherical lump under a dog's skin. It will usually appear haired, relatively soft and somewhat mobile, though variations in texture (firmer masses that are more firmly adhered to the underlying tissues) are not uncommon.

Should I worry about lumps on my dog? ›

It is important to get all new lumps checked out by your vet, however, to ensure that they are benign. Occasionally, lipomas will cause difficulty to your dog if they become involved with internal organs or if they become so large that they impede movement or make your pet uncomfortable.

What does a non cancerous tumor look like on a dog? ›

These growths often occur in overweight or older dogs, but they can appear as small lumps or bumps on the skin on any animal, appearing as hairless discoloured patches, or a growth the body. There are many types of tumors, which are caused by abnormal growth of the cells and affect the skin or the tissue in your dog.

What are these bumps on my dogs skin? ›

The most common types of lumps or bumps found on puppies are warts, skin tags, button tumors, and abscesses. In these cases, your vet may recommend a wart ointment or other skin treatment. There are also some products that claim to help dissolve normal fatty skin lumps on dogs.

What is the life expectancy of a dog with a mast cell tumor? ›

These tumors share a universally bad prognosis with survival times of less than 4 months. They behave aggressively and require more aggressive therapy. These tumors overall showed a median survival time of greater than 2 years but there were some tumors that behaved aggressively despite their low grade.

What are the fatty lumps on my dog? ›

A lipoma is a very common skin tumor found in dogs and is a benign accumulation of fat cells. Some dogs never have one, and others can be very lumpy because of multiple lipomas.

What foods cause lipomas in dogs? ›

Poor diet. Your dog's diet can actually lead to the development of a lipoma. Carbohydrates, chemical preservatives, and other toxins found in processed food all contribute to fatty tumor growth. Water is also an important part of your dog's diet.

Do dog lipomas appear suddenly? ›

As they grow larger, they can cause problems, such as tissue necrosis or discomfort for the dog. Can lipomas in dogs grow fast? Lipomas are traditionally slow-growing tumors. If you find a mass that seems to have appeared overnight, it is unlikely to be a lipoma.

How do I get rid of fatty lumps on my dog? ›

Treatment for fatty skin tumors in dogs may involve surgery, infiltration with calcium chloride, holistic/natural therapies, and a change in diet, such as feeding pet food specifically formulated for weight loss. Treatment for infiltrative fatty tumors requires surgery and radiation.

How long will a dog live with a cancerous lump? ›

It depends on how aggressive or advanced the particular cancer is. By the time it's detected, some dogs will live weeks to months, while others will live for years. Lymphoma patients, for instance, can live several years.

What percentage of lumps on dogs are cancerous? ›

Of submitted samples, 20% to 40% are reported to be malignant. The most common malignant skin tumors in dogs are mast cell tumors, soft tissue sarcomas, and squamous cell carcinomas.

Do cancerous bumps hurt dogs? ›

In dogs, the most common type of malignant skin cancer is a mast cell tumor. These tumors are superficial lumps that can be painful. They often swell, frequently bleed and then scab over, only to bleed again a few days later. They should not be squeezed by the owner, as squeezing can make them swell even more.

How often are lumps on dogs cancerous? ›

Fortunately, less than half of lumps on dogs are malignant, or cancerous, and most are treatable. In fact, lumps on or below the skin are the most common masses reported in dogs, representing roughly one third of all tumors.

How do I know if my dog's lump is benign? ›

There are two major types of lumps and bumps on dogs: malignant (cancerous) and benign (not cancerous). However, you can't tell the type or severity of a growth just by looking at it. A veterinarian can take a sample of cells to give you a diagnosis and appropriate treatment plan.

What do fatty lumps look like on dogs? ›

A lipoma will typically present initially as a small, hemispherical lump under a dog's skin. It will usually appear haired, relatively soft and somewhat mobile, though variations in texture (firmer masses that are more firmly adhered to the underlying tissues) are not uncommon.

Where are tumors most commonly found in dogs? ›

Skin tumors are among the most common tumors found in dogs and many are benign. Lymphoma. Lymphoma is a cancer of a type of blood cell (lymphocytes) and lymphoid tissues. Lymphoid tissue is normally present in many places in the body, including lymph nodes, spleen, liver, gastrointestinal tract and bone marrow.


1. When should I worry about a lump on my dog?
(Vet Candy)
2. Lumps, Masses and Bumps on Dogs' Skin | Dog Tips | Fetch by The Dodo
(Fetch by The Dodo)
3. When to Worry About a Lump on a Dog │ Dr. Sue Ettinger Deep Dive
(Dog Cancer Answers & Dog Cancer Survival Guide)
4. My Dog Has a Lump! Should I Be Worried?
(Dr Claire Stevens)
5. Lumps In Dogs And Cats: When To See The Vet, How To Treat At Home
(Veterinary Secrets)
6. Why does my dog have lumps and bumps? Ask Ben
(Online Vet Store)
Top Articles
Latest Posts
Article information

Author: Gregorio Kreiger

Last Updated: 04/07/2023

Views: 6669

Rating: 4.7 / 5 (77 voted)

Reviews: 92% of readers found this page helpful

Author information

Name: Gregorio Kreiger

Birthday: 1994-12-18

Address: 89212 Tracey Ramp, Sunside, MT 08453-0951

Phone: +9014805370218

Job: Customer Designer

Hobby: Mountain biking, Orienteering, Hiking, Sewing, Backpacking, Mushroom hunting, Backpacking

Introduction: My name is Gregorio Kreiger, I am a tender, brainy, enthusiastic, combative, agreeable, gentle, gentle person who loves writing and wants to share my knowledge and understanding with you.