Get

In Your Inbox

Catster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

What Causes Lumps on Cats? 6 Possible Causes & What to Do

Share

kitten with lump on skin

Imagine petting your cat and feeling something that doesn’t feel quite right. Is that a lump? Immediate concern and panic set in. As you pick up the phone to call your veterinarian, your mind is likely racing as to what this lump could possibly be. Continue reading below to learn more about six of the most common causes of lumps in cats.

divider 2 cats

The 6 Common Causes of Lumps on Cats:

1. Insect Bites

Fleas, ticks, and other insects can potentially bite or sting your companion, which can result in a lump or bump. Flea bites often cause several small bumps referred to as miliary dermatitis throughout their body, with a focus around the neck and tail base.

A single bump or localized swelling is more often found with other types of bites. In some cases, a palpable bump may actually be an attached tick. Appropriate preventative measures can help reduce the risk of parasitism.


2. Cancer

Unfortunately, some lumps that develop on your cat can be cancerous. Malignant growths can metastasize and cause problems elsewhere in the body. Depending on the type of growth present, surgical removal may be recommended. In cases where surgical removal is not an option, radiation may be beneficial.

Historically, a common cancer that cats developed was coined injection site sarcoma. This type of cancer was often associated with an inflammatory reaction that occurred secondary to vaccine adjuvants. Nowadays, this type of cancer is less common, as non-adjuvanted vaccinations have been developed and utilized.

cat being observed by a female veterinarian
Image Credit: David Herraez Calzada, Shutterstock

3. Benign Growths

Some growths that develop can be benign, or non-cancerous. A well-known type of benign growth is a lipoma or fat. Other types of growths can occur as well that do not impact other parts of the body and do not spread.


4. Abscess

When an infection occurs and is walled off within the body, an abscess is formed. Abscesses can form an obvious lump consisting of pus, which is often warm and painful to the touch. Abscess can form for a variety of reasons; however, one of the most common reasons is from fighting with other cats.

Abscess may need to be surgically addressed, whereas others may improve with antibiotics and pain medication. Animals with abscesses can often appear systemically ill, showing signs of lethargy, fever, and decreased appetite.

abscess on cat's neck
Image Credit: Elena11, Shutterstock

5. Inflammation

Injury or trauma can cause inflammation to occur that can palpate as a bump. Depending on the underlying cause of inflammation, your veterinarian will formulate a plan to help bring relief to your pet.


6. Lymph Node Enlargement

Lymph nodes are an important part of the immune system, as they house white blood cells that respond to infections. Lymph nodes can become enlarged because of a nearby infection, whereas other times they can be enlarged due to cancer. There are places where lymph nodes are readily palpable on the body, including under the chin, near the clavicle, and behind the knees.

vet checking up a cat with the owner
Image Credit: Stock-Asso, Shutterstock

divider 1 paws

Diagnosing a Lump

When you find a bump on your cat, the first step in understanding the cause is to schedule an appointment with your veterinarian. Your veterinarian will listen to your concerns, inquire about your cat’s history, and perform a thorough physical exam. Based on their findings and suspicions, recommendations will be given to provide the best care for your pet.

When a lump is found, especially if an underlying cause like parasites or trauma isn’t identified, a fine needle aspirate may be recommended. Obtaining a fine needle aspirate is achieved by introducing a needle connected to a syringe into a mass and pulling out a sample of cells. The cells are then placed on a slide and evaluated under the microscope. The cells are closely studied, and a diagnosis is made.

Sometimes, a diagnosis may not be definitive, and additional testing may be necessary. Additional testing may include a tissue biopsy, bloodwork, or ultrasound.

female vet checking up the cat
Image Credit: Ermolaev Alexander, Shutterstock

Treatment

Treatment for lumps and bumps on your cat will be dependent on the underlying diagnosis. Infections like abscesses will require antibiotics, whereas cancerous growths will likely require removal and possibly additional care. Close collaboration with your veterinarian is critical!

It is important to keep your veterinarian up to date with your pet’s progress. If things are not improving in the way that is anticipated, it is possible a different approach is necessary.

divider 2 cats

Conclusion

Cats can develop lumps and bumps for a variety of reasons. If a new bump suddenly arises or if your pet seems to be in discomfort, it is important to schedule a consultation with your vet. Your veterinarian will perform a physical examination to help determine the underlying cause and discuss treatment options.

See also:


Featured Image Credit: Mironmax Studio, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything cat

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.




How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Catster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Catster's Digital Magazine is Back!

Vet-approved health & behavior advice

Real cat stories & community features

Chatting About the Importance of Spaying/Neutering, Cat Retail Shopping Ban & Red-Level Storms | Chatty Cattys, Episode 30

In this episode of Catster’s Chatty Cattys podcast, Nicole and Dr. Karyn are celebrating a major legal win for pets before diving into...

Is Your Cat Happy? Here’s How You Can Tell

Cats have a reputation for being indifferent, even inscrutable. But despite their seemingly ambivalent appearance, cats experience many emotions, including happiness, and they...

Human Brains Age Like Cats – New Study Debunks the 7-Year Rule

If you’ve ever caught your senior cat staring blankly at a wall, wandering the halls at 3 am, calling out for no clear...

Chatting with Devin About Here! Have a Kitten, Fostering, & Why Two Are Better Than One | Chatty Cattys, Episode 29

In this episode of Catster’s Chatty Cattys podcast, Nicole & Dr. Karyn sit down with Devin, the founder and one-woman show behind “Here...

More related

Are Air Purifiers Safe for Cats? Vet-Approved Facts & Safety Tips

Air purifiers may sound too good to be true: a machine that can clean the air in your home? But a high-quality unit...

Can Cats Eat Radishes? Vet-Reviewed Facts & FAQ

We all know that cats are carnivores. However, we also know that some cats enjoy human foods, whether animal-derived or plant-based. Many cats...

Sentry Calming Collar for Cats Review 2026: Pros, Cons & FAQ

Review Summary The Sentry Calming Collar for cats works under the premise of cat pheromone science. Simply put, mother cats produce a pheromone...

“You Need More Sleep”: A Hilarious Author Interview

I have always prided myself on taking life advice from some of the most sagely sources around: maverick French soccer players, late-’80s hip-hop...

Keep reading

Ways to Discipline Your Cat: 5 Proven & Effective Methods (Vet-Verified)

Cats can be creative regarding the activities they enjoy, and their human companions don’t appreciate some of them. Cats sometimes scratch furniture to the point of destruction, jump on counters, and launch sneak attacks, which can lead pet parents to...

young man and brown tabby cat smell or looking each other

Why Do Cats Eat Their Vomit? Cat Behavior Explained!

Cats can often display behavior that is utterly baffling to their human companions. A common cat behavior that people tend to find odd is eating vomit. Many people have seen their cats chowing down on a pile of food that...

Munchkin cat eating

My Cat Takes Food Out of Their Bowl to Eat: 5 Vet-Reviewed Reasons

If you’ve ever had a cat for a pet, you may have seen them pawing the food out of their bowl, putting it on the floor, and then eating it. Sometimes a cat will even take the food and run...

cat by a bowl

My Cat Killed a Bird: What to Do & Prevention Tips (Vet-Verified)

If you have an outdoor cat, chances are there will be a time that they bring you a dead bird. This experience is unpleasant and certainly not something you would like to repeat. So, what do you do now? First,...

cat and bird

7 Most Annoying Sounds Cats Make: Possible Causes & Prevention Tips

Cats are adorable pets and can be some of the best companions and roommates. They look cute and can make cute sounds. In fact, some studies show that a cat’s purring may have therapeutic effects 1. However, there’s no denying...

Ginger tabby young cat sitting on a wooden floor looks up

Why Does Your Cat Sit on Things You Are Using? 4 Vet-Reviewed Reasons

What is the deal with your cat sitting on things you are using? There are countless videos on social media of individuals trying to work on the computer or read a book and their cat just wants to use it...

cat-books-Unsplash-photo-1627308722931-0e6a1214c03e

Can Cats Eat Butter? Vet-Approved Facts & FAQ

You probably found this article because you own a cat, and one of two things is true: they got into butter you left out, or you’ve heard that butter helps cats cough up hairballs. In either case, you might be...

Can Cats Eat Butter

Does Diatomaceous Earth Kill Fleas on Cats? Vet-Reviewed Effectiveness & Safety

Diatomaceous earth—a powdery substance made from fossilized algae—is growing in popularity as a chemical-free pest control method. But is it safe for pets? While diatomaceous earth is effective at killing fleas and can be used as part of an integrative...

diatomaceous earth

Love Cats? So Do We! Join the Catster Community

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.




Sign up for the Catster Email Newsletter

Stay informed with expert pet care insights delivered straight to your inbox! Discover professional guidance on animal behavior, feeding tips, trusted product picks, and much more.