What you need to know about lipomas

Lipomas are a common type of lump and are not cancerous. Around one in 100 people in the UK will develop a lipoma, which refers to a growth of fatty tissue that is usually contained within a fibrous capsule. 

Lipomas can develop anywhere in your body where you have fat cells; however, they most commonly occur on the arms, back of the neck, chest, legs and shoulder. 

Here, we’ll look at the different types of lipoma, symptoms and treatment. 

Types of lipoma

Conventional lipomas, which are the most common type of lipoma, contain only fat cells and develop in the fatty layer of your skin. 

However, there are several other types of lipoma named according to where they develop, the other types of cells they contain and their appearance. 

For example, intramuscular lipomas develop deep within a muscle; angiolipomas contain fat cells and blood vessels; fibrolipomas contain fat cells and fibrous tissue; and spindle cell lipomas comprise fat cells that are longer than those in traditional lipomas. 

Around one in 20 people with a lipoma will develop multiple lipomas — this is called familial multiple lipomatosis.

Who is at risk of lipomas?

Lipomas can develop at any age but are most common in those aged 40 to 60 years. 

The vast majority of individuals develop a solitary lipoma. However, as mentioned above, around one in 20 people with lipomas have familial multiple lipomatosis where multiple lipomas develop in different parts of the body — this is a rare, inherited condition and consequently, tends to run in families. 

There are no other known risk factors for developing a lipoma. Your ethnicity and skin tone do not affect your risk. 

Symptoms of a lipoma

Lipomas are usually soft, dome-shaped lumps that can move easily when touched. In most cases, they do not cause any symptoms or pain. 

However, depending on their size and location, you may find that your lipoma catches or rubs against your clothing. 

Very large lipomas, particularly those on the back or neck, can press against muscles or nerves and, therefore, cause discomfort or pain. 

Fibrolipomas often form along the gut and can, therefore, cause abdominal pain, nausea and/or bleeding if they block or apply pressure to part of your gut. 

Lipomas usually develop gradually over several months or sometimes years. If you notice a lump that is growing in size and/or is painful, it is important to see your GP to have it investigated. 

Diagnosing a lipoma

In most cases, a lipoma can be diagnosed by your GP through a physical examination. 

Your GP may recommend an ultrasound scan or MRI scan if your lipoma is larger than 5cm, located in deep tissue, causing you pain or changing in size.  

In rare cases, the results of your scan may suggest that your lump does not fit the features of a lipoma. Your doctor will then recommend that a tissue sample is collected (biopsy) for examination under a microscope. 

Treating lipomas

Lipomas do not usually go away on their own. However, if your lipoma isn’t bothering you, you don’t need to have it treated.  

If your lipoma is bothering you, it can be surgically removed. For small lumps, this is usually a day case procedure and is performed under a local anaesthetic. For larger lumps, surgery is performed under a general anaesthetic. 

It takes, on average, two weeks to recover from lipoma removal surgery. You will be left with a scar where the cut was made to remove your lipoma. 

In fewer than one in every 100 cases where a lipoma is removed, it returns in the same place.