Lump on Cat with Feline Fancy Logo.

Lumps on Cats | When to Worry and Seek Veterinary Care

Lumps on Cats

Discovering lumps and irregularities on your companion can cause concern for pet owners, like us; our informative handbook discusses various types of lumps found on cats and outlines steps to take if you come across one on your own cat.

It’s important to remember that not every lump on your cat’s skin is cancer. Cats can develop various types of lumps and bumps, and not all are a cause for concern. For instance, some lumps may simply be skin tags or lipomas, which are typically benign.

However, if your feline friend has a new lump, especially if it’s growing, changing color, or has an unusual shape, it’s crucial to consult your veterinarian. A thorough examination will help determine if the lump is a benign condition like a basal cell tumor or something more serious like a malignant tumor, such as a squamous cell carcinoma or a mast cell tumor.

Cat at vets being checked for lumps and bumps.

If a large lump has appeared on your cat overnight, especially if it’s located on the back near the spine or on the neck, your vet may suggest a fine needle aspirate or biopsy to confirm whether it’s a cancerous lump. Depending on the results, the treatment plan may involve surgical removal of the lump, chemotherapy, or radiation. Early detection and treatment are crucial for addressing any skin lumps on cats or potential risks.

For older cats or any lump that doesn’t respond to treatment, it’s important to stay in close contact with your vet to monitor the lump and adjust the treatment plan as needed.

Adult cat with lump on eye.

Common lumps on cats

Not all lumps and bumps on cats are the same. Here are some common types of lumps that veterinarians often encounter, including lumps on a cat's chin and lumps under the skin on cats:

Abscesses

Abscesses on cats are usually swollen puss filled areas that come from bites or scratches, normally from fights with other cats. They can be quite painful so your cat might be sensitive to touch around the area.


Cat Acne

Cat acne often starts with small, dark specks or bumps on your cat's chin. While it generally resolves on its own, severe or persistent cases may need treatment. For more details on Cat Acne and other Common Skin Issues, check out our article.


Cysts

These are small, raised bumps on your cat’s skin, often caused by blocked hair follicles or bacterial infections. A cyst on a cat might appear anywhere on their body, such as a lump on the cat's neck or a lump on the kitten's back.

Insect Bites and Stings

Just like in humans, insect bites or stings can cause swelling and redness in cats. A flea bite, for example, might be mistaken for a skin lump. For more details on The Best Flea Treatment for Cats, check out our article.

Tumors

Cats can develop various types of tumors, some of which might be cancerous. These lumps can appear anywhere on your cat’s body, including the lump on the cat’s side near the ribs or a lump on the cat’s tail.

Reactions to Injections

If your cat develops swelling post injection similar to a vaccine shot and it persists without improvement it is advisable to seek advice from your veterinarian regarding this issue. The swelling could manifest as a lump, on the cats neck or side that shows no signs of resolving.

A lump under the skin of a cat, possible cancer growth.

How does my vet determine what the lump is?

After gathering detailed information from you about the lump and your cat's overall health, your vet will conduct a thorough physical examination, carefully inspecting the lump. Some cat lumps, like abscesses, may be identifiable through examination alone, but others, such as a fast-growing lump on a cat, might require additional testing.


The most common initial test for lumps is a fine needle aspirate (FNA). During this process your vet will insert a needle into the lump, whether it's a lump on the cat's belly, chin, or leg to collect a sample of cells. These cells are then placed onto a microscope slide, stained with special dyes, and examined under a microscope. Sometimes, a diagnosis can be made immediately, but in other cases, the slide may be sent to a specialist veterinary pathologist for further analysis.


For other types of lumps, such as a hard lump on a cat’s neck or a lump under a cat's armpit, a tissue biopsy may be necessary. This short procedure, performed under general anesthesia, involves removing a tissue sample, which is then sent to a lab for testing. Additional diagnostic tests for skin conditions include skin scrapes, hair plucks, and bacterial or fungal cultures to determine if there is an infection and identify its cause.


This process is important for finding the cause, like a hard lump on a cat's lower jaw, a lump on the back of a cat’s neck, or lumps on a cat's head.

A ragdoll cat with a reddish lump showing through fur above right leg.

Skin tumors and cancerous lumps on cats

There are two types of growths that might be found on your cat’s body: benign (non-cancerous) and malignant (cancerous).

Lipomas

Lipomas are non-cancerous, fatty tumors that can appear anywhere on your cat’s body, such as a lump on a cat’s leg or a small lump on a cat’s neck. These are more common in older or overweight cats. Although they are generally harmless, they can cause issues if they are in a location that interferes with your cat’s movement. For more information on managing your cat’s weight, please visit our advice pages.

Cancerous lumps

Cancerous lumps can also develop in any place, such as a lump on a cat's back, a lump on a cat's lip, or a bump on a cat's head. If you discover a new growth on your cat, whether it’s a lump behind the ear or a lump on a kitten’s neck, it’s important to have it checked by your local vet.



It’s not possible to determine if a lump is cancerous just by looking at it, so your vet may need to conduct tests. This might include taking a cell sample from the lump, like a cyst on a cat's head or a lump on a cat's face, using a needle. While this procedure may be briefly uncomfortable for your cat, it’s usually quick. In some cases, a larger sample or the entire lump may need to be removed for further analysis, especially if it’s a suspicious area like a cat’s swollen chin or a black lump on a cat.

Close up of suspected cancerous lump.

Treatment of lumps

The treatment advised by your vet will depend on the cause of your cat's lump or bump. For common causes of cat skin lumps, such as lipomas or skin tumors, treatments may include surgical removal, especially if it's a malignant tumor like a mast cell tumor, squamous cell carcinoma, or basal cell carcinoma. Medications, such as antibiotics, antifungal drugs, and anti-inflammatory treatments, might also be used depending on the specific type of lump and its cause. In some cases, your vet may suggest monitoring the skin lump, particularly if it’s in an older cat struggling with dementia or a slow-growing lipoma.


If the lump is suspected to be a cell tumor, like a mast cell tumor, a fine needle aspiration might be performed to confirm the diagnosis. This involves taking a sample from the lump to check for malignant cells. Surrounding tissue may also be examined to ensure the tumor hasn’t spread. In cases where a malignant tumor is confirmed, surgery to remove the tumor is often recommended to prevent further spread. Veterinary oncologists can provide specialized care for cats and dogs living with cancer. Understanding the common causes and risk factors for these skin conditions can help in early detection and effective treatment.

What to do if you find a lump on your cat

If you discover a new lump on your cat, it’s important to schedule an appointment with your vet as soon as possible. All new lumps or bumps should be evaluated by your veterinarian, as they are best equipped to determine the type of lump and recommend appropriate treatment, whether it involves surgical removal or other therapies.


Avoid taking a ‘wait and see’ approach, as some lumps—especially those that are infected or related to a malignant tumor like a mast cell tumor or squamous cell carcinoma—may require immediate medical attention. Delaying treatment for a cancerous lump could allow the cancer to spread to surrounding tissue or other areas, increasing the risk for your cat. Early detection and prompt action are crucial in managing the common causes of skin lumps in cats.

British Shorthair cat that is having a full health check up at vets.

Can I reduce the risk of my cat developing certain lumps or bumps?

Keeping your cat safely indoors with access to a secure outdoor enclosure can significantly reduce the risk of lump on a cat’s skin from cat fight abscesses or injuries from accidents.


Having your cat desexed before puberty (before four months of age) offers many benefits, including a reduced risk of mammary cancer in female cats.


Establish a routine early on, regularly grooming your kitten and gently checking for any abnormalities, such as a lump on a kitten’s belly or bumps on a cat’s skin. Familiarizing yourself with what is normal for your cat will help you quickly identify anything unusual, such as a lump behind a cat's ear, a lump above a cat's eye, or lumps under a cat's chin. Early detection of a lump or bump and prompt veterinary examination are crucial.


When you notice a lump, such as a lump on a cat's leg or a lump on a cat's tail, it’s helpful for your vet if you can provide details about when you first saw it, whether it is growing, and if that growth is rapid or slow. This information is particularly important for distinguishing between a cat lipoma vs cancer or monitoring something like a cat cyst on the head. Additionally, if your cat shows signs of being unwell along with the appearance of a lump, such as cat swelling under the chin, it’s essential to seek veterinary care immediately.

Treating lumps on cats

The treatment for your cat’s lumps or bumps will depend entirely on their type and underlying cause. Potential treatments may include:


  • Antibiotics - for infected lumps, such as abscesses.
  • Draining the lump - which may be necessary for an infected abscess.
  • Anti-inflammatories - and other forms of pain relief to manage discomfort.
  • Changing your cat’s food - if the lumps are due to a food allergy.
  • Surgical removal - of skin tumors or lumps. Surgery may be suggested for both benign growths, like a lipoma cat, or malignant tumors, such as squamous cell carcinoma, mast cell tumors, or basal cell carcinoma.
  • Steroids and chemotherapy - for treating cancerous lumps, including cell carcinoma and other types of malignant tumors.
  • Monitoring - where your vet may ask you to keep an eye on the skin lump, noting any changes in size, texture, or if it starts causing your cat pain, and report these changes. This might involve using a fine needle to confirm diagnosis or check for involvement of the lymph node or surrounding tissue.

Early detection and appropriate treatment are key to managing skin conditions and tumors in cats, especially for old cats or those with slow-growing lumps. Always follow your veterinarian’s recommendations for the best outcome.

A lump & bump on cats front.

Identifying lumps and bumps early

Many of us enjoy spending time relaxing and bonding with our cats, which is the perfect opportunity to examine their skin for any lumps or bumps. During these moments, you might notice something unusual, such as a cat lump on the stomach, bumps on cat’s skin, or even a cat mass. If you find any abnormal growths, like lipomas in cats, a fatty tumor, or a lump in the cat’s stomach, it’s important to book a vet appointment promptly.

For issues like a cat chin swollen or cat swollen face cancer, or if you see black spots on a cat’s skin under fur, don’t wait. Also, if you notice something like a cat bump on the nose or a growth on the cat’s paw, it’s wise to have them checked. Even seemingly minor issues, such as a cat pimple or a cat mouth cyst, should be evaluated by a veterinarian to rule out any serious conditions, including benign tumors or cat tumors.

Are cancerous lumps on cats hard or soft?

In cats with growth on their bodies can have lumps that feel either firm or soft, to the touch; the texture can differ based on the specific type of cancer and where the lump is located on their body.

Hard Lumps

Allot of cancerous tumors such as cat skin tumors or lipomas in cats, can feel firm or hard. A lump in the cat’s stomach or a cat tumor belly might be solid and firm.

Soft Lumps

Some cancerous lumps might feel softer or more pliable. For example, if you notice a spot on your cat’s chin or spots on cats that are soft and fluid-filled, it could be due to conditions like cat acne, which can be painful and might lead to cat sore chin.



If you find any new lumps, such as a kitten with a lump on the side of the stomach or a cat lump after vaccination, it’s important to take them to your local vet. Whether the lump is a pimple on a cat, a black spot under your cat’s chin, or parasitic lumps on cats, catching it early is very important.


For issues like a cat bite by another cat, which might lead to a swollen face or sudden lump on the forehead overnight, or if you're dealing with a cyst on a cat and wondering how to drain a cyst on a cat, professional veterinary care is recommended.

Large hard growth under cats chin.

FAQ

Should I worry about a lump on my cat?

Yes, you should have a lump on your cat checked by a veterinarian. While it could be a common type of lump like a skin tag or a slow-growing tumor, it might also be skin cancer or related to issues like an enlarged lymph node. Early diagnosis and appropriate treatment, including surgery to remove the lump if necessary, are important. Your vet can recommend the best course of action, which might include anti-inflammatory medications if the lump is causing discomfort.

How can you tell if a lump on a cat is cancerous?

To determine if a lump on a cat is cancerous, a vet will usually perform a fine needle aspiration (FNA) to analyze the cells or a biopsy to examine tissue samples. They may also use imaging techniques and monitor any bumps on the cat for changes in size or texture.

Why does my cat have a lump on her stomach?

A lump on your cat's stomach could be due to various reasons, including lipomas, cysts, tumors, or abscesses. Common causes of a skin lump include risk factors like age or weight. It's important to have a vet assess the lump to determine the underlying cause and recommend appropriate treatment. this is the same answer for the following questions - why does my cat have a lump on his back, why does my cat have a lump on his neck, why does my cat have a lump on her leg, why does my cat have a lump on his side.

Is there a reason my cat would have lumps besides cancer?

Yes, there are several reasons a cat might have lumps besides cancer. Common causes include lipomas (benign fatty tumors), cysts (fluid-filled sacs), and abscesses (often from infections or injuries). Skin tags and parasites can also lead to lumps or bumps on your cat's skin. Additionally, inflammatory reactions or allergic responses can cause swelling or lumps. It's important to have any lump evaluated by a vet to determine its cause and ensure proper treatment.

Why does my Cat have a lump one month after rabies vaccine?

A lump one month after a rabies vaccine is often a benign reaction, such as a localized injection site reaction or swelling. This can occur as a normal response to the vaccine. However, if the lump persists or changes, it’s best to have a vet check it to rule out any complications or other issues.

How can you treat a sebaceous cyst on your cat?

To treat a sebaceous cyst on your cat, a vet may recommend several approaches. Typically, treatment involves surgical removal of the cyst to prevent recurrence and to ensure it doesn't become infected. In some cases, if the cyst is small and not causing any issues, your vet might suggest monitoring it and may recommend antibiotics if there's any sign of infection. Warm compresses can sometimes help if the cyst is inflamed. Always consult with a veterinarian for the best treatment plan tailored to your cat's specific condition.

Do lumps on cats go away on their own?

Some lumps on cats may resolve on their own, particularly if they are benign, such as minor cysts or abscesses. However, it's essential to have any new or changing lumps evaluated by a vet to rule out serious conditions like cancer and to determine the appropriate treatment.


Kelly Rushton with her cat Eddie Stafford.

Kelly Rushton

Meet Kelly Rushton, a dedicated cat enthusiast and proud owner of Feline Fancy Ltd. With a heart as big as her household, Kelly is the loving mum to 10 charming Ragdoll cats. In her world, felines reign supreme, and she brings professionalism and warmth to everything she does. Through her blog, Kelly shares her wealth of knowledge and experiences, offering insights into cat care, behavior, and the joy of living alongside these majestic creatures.


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