Lipoma: What Is It, Symptoms, Causes & Treatment

Updated in June 2023

A lipoma is a type of benign tumor that is formed by fat cells. It can appear anywhere on the body, however the most common areas to find a lipoma include the shoulders, chest, back, neck, thigh and armpit. In some cases, they may develop on internal organs, bones or muscles.

A lipoma is characterized by a round lump that grows over time. It can cause physical discomfort, as well as an unpleasing look. However, it is considered to be benign and is not related to cancer. In very rare cases, it can transform into a liposarcoma.  

Generally, treatment is not needed, however for cosmetic reasons it may be removed. Lipomas that become painful or grow very rapidly can also be indications for surgical removal. 

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Common symptoms

The main signs and symptoms of a lipoma are: 

  • A round lump beneath the skin, mainly in the neck, back, shoulders and abdomen. 
  • Not painful, but uncomfortable when palpated
  • A firm, elastic and/or smooth consistency
  • A small lump, around 5 cm that can grow up to 10 cm, which is considered to be large enough for removal 

Lipomas can grow over time without causing any harm. Larger lipomas can press on or obstruct tissue that surrounds it, causing symptoms like pain, redness or increased temperature in the area.

Can lipomas be malignant?

A lipoma is a tumor made of fat cells that is found beneath the skin. These are generally harmless. In very rare cases, it can transform into a liposcarcoma, which is a malignant tumor that starts as fatty tissue and can spread to the skin or muscles. These can cause symptoms like pain and swelling, and are most found in the arms, legs and abdomen. 

Confirming a diagnosis

A lipoma diagnosis can be confirmed by a dermatologist through clinical assessment and biopsy. Lipomas that are large can be visualized with imaging tests, like X-ray, MRI, or CT. These can help to verify the lipoma's characteristics and determine whether it is deep and affecting other tissues.

Though testing, it is also possible for the doctor to differentiate a lipoma from a sebaceous cyst, which is also a type of lump under the skin but is formed by sebum. Sebum is a fatty substance secreted by sebaceous glands in the skin. Sebaceous cysts can present very similarly to lipomas.  

Possible causes

The exact cause of a lipoma is not well understood and can occur in both men and women at any age (although they are more common in adults between 40 and 60 years of age). These are rarely found in children. All lipomas should be evaluated by a dermatologist. 

Some factors that can contribute to the development of a lipoma include: 

  • Family history of lipomas
  • Gardner's syndrome
  • Cowden's syndrome
  • Madelung's syndrome 

In addition, anther condition that can cause lipomas includes familial multiple lipomatosis, in which the patient presents with various lumps that are large and painful.  

Treatment options

Generally, lipomas do not require any treatment. However, if they are cosmetically unpleasing or if the lipoma is large, painful and impeding with activities of daily living, the doctor may remove it surgically. 

1. Surgery

Surgery for lipoma removal consists of a small incision on the skin under local anesthetic (although very large lipomas may be removed under general anesthesia). The lump is then removed through the small incision. 

Surgery is safe and very effective, and the lipomas rarely regrow. The patient typically has the surgery and is discharged home the same day. 

Following surgery, the doctor may prescribe analgesics to relieve pain and discomfort in the area. He or she may also prescribe ointments to speed up skin healing and prevent scarring. 

2. Liposuction

Lipomas can also be removed through liposuction. This involves the insertion of a needle and syringe in the lipoma area to remove fat cells in the area. This can also be done under local anesthesia. 

Liposuction is a very effective surgery that is less risky and boasts a speed recovery. However, the lipoma is at a slightly higher risk to regrow when compared to surgical removal.