• Types
• Symptoms
• Causes
• Risk factors
• Diagnosis
• Removal
• Contacting a doctor
• Summary

A lipoma is a lump under the skin that occurs due to an overgrowth of fat cells. Lipomas are typically harmless but people may wish to remove one that causes pain, complications, or other symptoms

Lipomas can occur anywhere on the body where fat cells are present, but they tend to appear on the shoulders, chest, trunk, neck, thighs, and armpits. In less common cases, they may form in internal organs, bones, or muscles.

Lipomas feel soft and may move slightly under the skin when people press down on them. They usually grow slowly over months or years and typically grow between 1 and 10 centimeters (cm)Trusted Source.

Types of lipoma

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Lipomas are benign masses of fat cells. There are several subtypes of lipoma, such asTrusted Source:

• angiolipomas
• angiomyolipomas
• myelolipomas
• fibrolipomas
• hibernomas
• ossifying lipoma
• spindle cell lipomas
• pleomorphic lipomas
• chondroid lipomas
• neural fibrolipomas

Lipomas are not the same as liposarcomas. Liposarcomas are a cancerous mass of fat cells. Lipomas cannot turn into liposarcomas, but the two types of tumors can look very similar.

Symptoms of lipoma

A person with a lipoma will typically feel a soft, oval-shaped lump just beneath the skin. Lipomas are usuallyTrusted Source painless and do not cause other symptoms.

Someone with a lipoma that occurs deeper under the skin may not be able to see or feel it.

However, a deep lipoma may place pressure on internal organs or nerves and cause associated symptoms. For example, a person with a lipoma on or near the bowels may experience nausea, vomiting, and constipation.

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What causes a lipoma?

Experts do not fullyTrusted Source understand what causes a lipoma.

Some people inherit a faulty gene from their parents that can cause one or more lipomas. This is rare and is known as familial multiple lipomatosis.

Researchers associateTrusted Source lipomas with some medical conditions, including:

• Gardner’s syndrome
• Cowden syndrome
• Madelung’s disease
• adiposis dolorosa

Some lipomas may also result from an injury that involves a substantial impact on the area.

Risk factors for lipoma

Lipomas are fairly common. Experts estimate that around 1%Trusted Source of people have a lipoma and that they are typically underreported.

People who have a family relative with one or more lipomas may have a higher risk of developing them. They may also be more likely to occur in people ages 40 to 60.

Other risk factors for developing a lipoma may includeTrusted Source:

• obesity
• high cholesterol
• diabetes

Diagnosing lipomas

For lipomas that are not too deep, doctors may be able to make a diagnosis with a simple physical examination. This will involve looking at and feeling the lump. If the lipoma is large or painful, the doctor may order tests to check if it is cancerous.

They may also use the following tests for lipomas that are deeper:

• ultrasound scan
• MRI scan
• CT scan

In some cases, a doctor will perform a biopsy. They will remove a small sample of cells from the lump and examine the tissue under a microscope to look for signs of cancer.

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When is lipoma removal necessary?

Lipomas are usuallyTrusted Source harmless, so most people do not need to have surgery to remove them. People may choose surgical removal if the lump:

• is cancerous
• is large or growing quickly
• causes bothersome symptoms, such as pain and discomfort
• interferes with body functions
• causes distress for cosmetic reasons
• the doctor is unable to confirm it is a lipoma rather than another type of tumor

Lipoma removal procedure

A doctor can usuallyTrusted Source remove a lipoma surgically. One method is to make a small cut in the skin and then squeeze out the lipoma. The person is usually under local anesthesia during the procedure and should be able to return home on the same day.

A doctor may need to make a more significant incision to remove larger lipomas entirely, and liposuction may be necessary.

To use liposuction, the doctor will need to cut into the lump and insert a thin, hollow tube through the incision. They will then use the tube to suck the mass of fat cells out of the body.

After surgery, the doctor may send the lipoma material to a laboratory for analysis to make sure that it is definitely a lipoma and not a cancerous tumor.

When to see a doctor

People should always tell their doctor if they notice changes in a lipoma or if more lumps appear. These changes might involve the lipoma:

• increasing in size or suddenly growing very quickly
• being painful
• becoming red or hot
• turning into a hard or immovable lump
• causing visible changes in the overlying skin

Summary

Lipomas are harmless, fatty tumors that can form under the skin. They are usually painless and do not require treatment. However, a doctor can surgically remove a lipoma if it causes pain or other symptoms or if someone wants to get rid of it for cosmetic reasons.

Fatty tumors can be benign or cancerous. However, most experts agree that lipomas do not usually become cancerous. It is essential to seek medical advice if a lipoma becomes painful, gets larger, or changes in any other way.

Doctors may be able to diagnose a lipoma with a physical exam, but in some cases, they may need to perform a biopsy and send tissue to a lab to ensure the tumor is not cancerous.