Lipomas are non cancerous lumps caused by an overgrowth of fat cells. Find out more about lipomas and the treatment.
What is it
A lipoma is a non cancerous (benign) lump that forms due to an overgrowth of fat cells. You can get a lipoma anywhere on the body where you have fat cells.
Lipomas are not cancer. Cancerous tumours of the fat cells are called liposarcomas. They are a type of soft tissue sarcoma. In most cases, these do not start from a lipoma.
It is very rare for lipomas to turn into a cancerous sarcoma. It is still important to tell your doctor if your lipoma changes in any way or if you get any new lumps.
Who gets it
Lipomas are fairly common. About 1 in 100 people (1%) will develop a lipoma.
We don’t know what causes them, but some people develop them because of an inherited faulty gene. This condition is known as familial multiple lipomatosis and is not common.
People with familial multiple lipomatosis will develop more than one lipoma. The exact number they have can vary but it can be several or many.
Lipomas are usually just under the skin, and feel soft to touch. They are usually shaped like a dome.
Most lipomas don’t cause any pain or other symptoms but this depends on where in the body it is. If a lipoma is deeper inside your body, you won’t be able to see or feel it but it might press on other organs or nerves.
For example, a lipoma might affect the bowel and can cause a blockage. If this happens you may become constipated and feel sick.
To make a diagnosis your doctor will feel and look at your lump. In most cases your doctor can recognise and diagnose a lipoma easily. Sometimes you might need an ultrasound scan of the area.
If any lipoma increases in size or becomes painful, you must tell the doctor, as it can be a sign that the lipoma is changing.
Rarely, doctors can’t tell for certain whether the lump is a lipoma or not. Lipomas can be confused with malignant (cancerous) tumours, called liposarcomas.
Your doctor may feel it is best to remove it or take a biopsy so that they can be certain it is a lipoma, and arrange a referral to a specialist.
Lipomas don’t usually need removing. But in some cases you, or your doctor, might want your lipoma removed. This might be because:
- your doctor wants to be certain it is a lipoma
- your lipoma is large, or is growing larger
- your lipoma is causing symptoms, for example by pressing on a nerve, or blocking the bowel
- you may want to have your lipoma removed for cosmetic reasons
You usually need a small operation under local anaesthetic to remove a lipoma that’s under the skin. You might have a very slight scar once the wound has healed.
The removed lipoma should then be sent to the laboratory for analysis.