What Is a Lipoma?
A lipoma is a lump of fat that grows in your body’s soft tissues. Though it’s classified as a tumor, it’s usually harmless.
It’s the most common tumor to form beneath your skin. About 1 out of every 1,000 will get one at some point. You most often find them in your upper body, arms, or thighs.
Lipoma Symptoms
They usually appear as small, soft lumps. They’re typically less than 2 inches wide. You could have more than one.
When you press on the lipoma, it may feel doughy. It will move easily with finger pressure. They don’t normally hurt, but they can cause pain if they bump against nearby nerves or have blood vessels running through them. Here are some characteristics of a typical lipoma:
- Found under the skin: Lipomas can be found anywhere in the body where there is fat, but they often show up in the shoulders, chest, back, belly, arms, and, sometimes, legs.
- Soft and small: They usually appear as small, soft lumps. They’re typically less than 2 inches wide. You could have more than one.
- Feels doughy and slips: When you press on the lipoma, it may feel doughy. It will move easily with finger pressure.
- Usually painless: They don’t normally hurt, but they can cause pain if they bump against nearby nerves or have blood vessels running through them.
- Stays in a single spot: They have a thin, fibrous covering and do not spread to the nearby tissues.
- Slow-growing: They grow slowly and will stop growing after a point.
Lipoma locations
You can find a lipoma on any part of your body, but it’s less likely to grow in the muscles, internal organs, or brain.
Lipomas often form under the skin on the following areas:
- Shoulders
- Chest
- Back
- Belly
- Arms
- Legs
Most people will have one lipoma, but about 5%-10% of people with it have more than one.
Types of Lipomas
Although all lipomas have fat in them, they vary depending on:
- What type of fat is in them
- Whether they also have blood vessels in them
- Where they are located
Types of lipomas
- Conventional. This lipoma has white fat cells (cells that store and release energy) in them. They’re the most common type of lipoma.
- Spindle cell lipoma. This type has long and slender fat cells.
- Intramuscular lipoma. These are found in the muscles and are rare.
- Angiolipoma. This lipoma has fat cells and blood vessels in it. This type makes up 5%-17% of lipomas.
- Hibernoma. This lipoma has brown fat cells (cells that create heat and regulate body temperature). They are rare.
Other types of lipomas
- Fibrolipoma
- Myelolipoma
- Pleomorphic
- Intermuscular lipoma
- Parosteal or periosteal lipoma
- Lipoma arborescens
- Intracranial lipoma
Lipoma Causes
It isn’t clear what causes them. However, researchers have noticed that
- Middle-aged men and women tend to get them more.
- They run in families.
- They often show up after an injury, though doctors don’t know whether that’s what makes them form.
Lipoma may also occur as a symptom of some rare health conditions. These conditions include:
- Dercum’s disease: This rare disorder causes many painful lipomas to grow on different body parts such as your upper arms, legs, trunk, and muscles.
- Gardner syndrome: This rare disorder that runs in families causes lipomas to grow in many areas of the body, such as the stomach.
- Madelung’s disease: This rare condition causes lipomas to appear in the neck, upper arms, shoulders, trunk, hips, and thighs. It often happens in people assigned male at birth aged 30-70 who take or used to take too much alcohol. It can also occur in people assigned female at birth who don’t drink alcohol.
- Hereditary multiple lipomatosis: This condition causes painless lipomas to grow on the trunk, arms, and legs. It runs in families and is also called familial multiple lipomatosis.
How common are they?
Lipomas are common. About 1 out of every 1,000 people will get one at some point. They’re the most common tumors that form under your skin.
When to Call a Doctor
If you notice a lump or swelling on your body, have a doctor check it out. They can let you know whether it’s a harmless lipoma or something that needs more tests.
Lipomas can form inside muscles or internal organs, but this doesn’t happen often. If one is causing pain or affecting your muscles, you might have to get it removed.
It’s rare, but a lump may be a type of cancer called liposarcoma, which grows rapidly and can be painful. If your doctor thinks you may have this condition, they’ll suggest more tests.
Lipoma Diagnosis
Lipomas can usually be diagnosed with a physical exam. But you may need a biopsy, in which a small piece of the tissue is removed and looked at under a microscope, to confirm the diagnosis. Tests such as X-rays, CT scans, and MRIs can also give a clearer picture.
Lipoma ultrasound
An ultrasound can help a doctor confirm:
- If the growth under your skin is a lipoma
- How big and deep the lipoma is
- If the lipoma has any features that suggest it isn’t a healthy or normal growth
Lipoma vs. liposarcoma
Liposarcoma is a rare cancer that starts in fat cells. It usually causes no symptoms, but you might see a painless lump under your skin. Later, this lump may become painful, and you might notice swelling and numbness around it. This condition is life-threatening. A doctor can remove the lump with surgery and then treat it with radiation or chemotherapy. See a doctor if you notice any lumps in your body, and they can let you know if they are harmless or need treatment.
A lipoma, on the other hand, is a fatty lump that usually stops growing at a point and causes no other symptoms. It usually doesn't need treatment unless it changes how the area looks or becomes painful.
Lipoma vs. cyst
Like lipomas, cysts are lumps under the skin that may show up on your face, neck, trunk, or other body parts. But these lumps have fluid, air, or pus and may open with a tiny black head. They can feel swollen and tender. Although they are harmless, they can become inflamed and infected.
A lipoma is a fatty lump that grows under the skin and never appears outside the skin. It is harmless and painless, too.
Lipoma Removal and Treatment
As lipomas aren’t harmful, doctors often leave them alone. You may need to keep an eye on it between visits.
If it hurts or you don’t like the way it looks, you might want to have it removed. Your doctor can take it out surgically with a small cut. You’ll get a shot of medication to numb the area so it won’t hurt. You should be able to go home after it’s done. You may have to go back within a couple of weeks to get a few stitches taken out.
Other possible treatments include:
- Steroids: This type of drug can help shrink a tumor.
- Liposuction: The doctor uses a needle and syringe to draw out the fatty tissue.
Lipoma removal cost
It may cost about $2,000 to $5,000 to remove a lipoma through surgery. How much you will pay will depend on:
- Where the lipoma is
- How big it is
- How deep it is
Insurance may cover removing a lipoma if they think it is medically necessary. Contact your insurance provider to confirm if they’ll cover it.
Large Lipomas
Lipomas bigger than 2 inches are sometimes called giant lipomas. They can cause nerve pain, make you feel self-conscious about your looks, or change the way your clothes fit.
It’s a little harder to take out one of these. The doctor will probably give you medication that will help you sleep through the procedure. You’ll need someone to drive you home afterward.
Lipomas rarely come back once removed. Having one doesn’t make it more likely that you’ll get other diseases.
Takeaway
A lipoma is a harmless fatty lump that grows slowly in the body's soft tissues. It's usually soft, small, and painless. You can find it anywhere on your body, but if you have it, it’ll likely be on your arms, shoulders, chest, back, or belly. However, see a doctor if you find any lumps on your body. They can tell you if it needs to be treated.
Lipoma FAQs
Can lipomas become cancerous?
Yes, lipomas can become cancerous, but this rarely happens. A lipoma that becomes cancerous is called liposarcoma. See a doctor if you notice any changes in how your lipoma lump feels and looks. They will do tests, such as a biopsy, to confirm if it is cancerous.
How do you get rid of lipomas?
A doctor can get rid of a lipoma through surgery, using a small cut to remove it. They may also recommend steroid medicine to shrink it or a liposuction procedure to draw out the fat.
What happens if the lipoma is left untreated?
Nothing will happen if a lipoma is left untreated. But see a doctor if the lipoma changes size, shape, and feel. They can tell you if you need treatment.