Definition

A lipoma is a round or oval-shaped lump or tumor filled with fatty tissue that grows just under the skin. Lipoma lumps are mobile when touched and generally do not cause any pain. Lipomas can appear anywhere on the body, but are most common on the back, torso, arms, shoulders and neck. In rare cases, lipomas can also form in internal organs, bones or muscles. Lipomas are benign soft tissue tumors that grow slowly and are not cancerous, so they are usually harmless.

Lipomas are very common, with an estimated 1 in every 1,000 people developing a lipoma. Lipomas most commonly appear between the ages of 40 to 60, but can occur at any age. Some patients can also have more than one lipoma. Lipomas can be experienced by people of all genders, but are slightly more common in women.

Causes

The cause of lipoma is not known for certain. Lipomas are thought to run in families, which means that if you have a family member with a lipoma, your chances of developing one might be increased. It is thought that the appearance of lipomas often occurs in areas of the body that have been injured, although the mechanism of this is not known.

Risk factor

Some factors that will increase your risk of developing a lipoma include:

• Aged between 40 and 60 years old. Although lipomas can occur at any age, they are most common in this age group.
• Genetic factors. Lipomas tend to run in families.
• Certain medical conditions. Some conditions can increase the risk of multiple lipomas to form on the body, such as:
• Dercum disease: This rare disorder can cause painful lipomas to grow and most commonly develop on the arms, legs and torso. This disease is also known as Adiposis Dolorosa or Anders Syndrome.
• Gardner syndrome: A type of disorder called Familial Adenomatous Polyposis (FAP), which can cause lipomas and other various health problems.
• Hereditary Multiple Lipomatosis: Also called familial multiple lipomatosis, this disorder is inherited (passed down through families).
• Madelung disease, also known as double symmetrical lipomatosis, is a condition that most commonly occurs in men who drink alcohol excessively and causes lipomas to grow around the neck and shoulders.
• Obesity
• Diabetes
• High cholesterol levels
• Liver disease

Symptoms

Lipomas can grow anywhere in the body. In rare cases, lipomas can grow in muscles, internal organs, or the brain. Most people with lipomas have only one lipoma lump, although more than one lipoma can grow. Most lipomas develop just under the skin in these areas:

• Upper or lower extremities 
• Back
• Neck
• Shoulder
• Upper body (chest and abdomen)
• Forehead

The signs and symptoms of a lipoma are usually a lump with these characteristics:

• Located just under the skin.
• Have a round or oval shape and the lump is usually symmetrical.
• Have the same color as the surrounding skin surface.
• It is soft and rubbery to the touch, the lump can also move easily with slight finger pressure.
• Generally small in size. Lipomas are usually less than 2 inches (5 centimeters) in diameter, but can still grow larger.
• It is not painful, but can sometimes cause pain. Lipomas can be painful if they grow and press on nearby nerves or if they contain many blood vessels.
• Localized (encapsulated), meaning the lipoma does not spread to surrounding tissues.
• It grows slowly.

Diagnosis

In diagnosing lipoma, the doctor will start by conducting an anamnesis with you. They will ask you about the symptoms you are experiencing, how long the lump has been there, the location of growth, whether the lump is accompanied by pain, and they will also ask about your medical history of other diseases you previously had. 

Next, the doctor will perform a physical examination by inspecting the growing lump directly. They may also palpate the lump to assess the surface and texture of the lump, as well as examine if there is tenderness and mobility of the lump. The diagnosis of lipoma can be established with anamnesis and physical examination, as lipomas have fairly specific clinical appearance. However, the doctor may suggest some diagnostic tests to further confirm the diagnosis and rule out other possible causes, such as:

• Biopsy examination can be performed to confirm that lipoma is not cancerous. In biopsy, the doctor will take a small sample of lipoma tissue and send it to the laboratory to be tested.
• Imaging tests. Often, the lump may be mistaken for a cyst (fluid-filled pouch). To see a clear image of the lump, the doctor may perform imaging tests such as an ultrasound (USG), MRI scan, or CT scan. These imaging tests can help the doctor determine whether the lump is a lipoma or a cyst. These tests can also help identify the location of the lipoma and how deep it is located if it has blood vessels and if the lump is pressing on nerves or other tissues.

Management

Lipomas are usually harmless, so most cases do not require special treatment or therapy. Lipomas may require management if:

• The lump is suspected of being cancerous
• It has large size or growing rapidly
• Causes upsetting symptoms, such as pain and discomfort
• Interferes with the normal functioning of the body
• Causes distress for cosmetic reasons
• The lump cannot be confirmed if it is a lipoma or other type of tumor

Some of the options for lipoma management include:

• Surgical Removal. Most lipomas are surgically removed with excision. Recurrence after tumor removal is rare. Possible side effects are scarring and bruising. A technique known as minimal excision extraction may result in fewer scars. Before undergoing the surgical procedure, the area around the lipoma will be given a local anesthetic. This procedure is safe, and effective and can be done on an outpatient basis.
• Liposuction. This procedure uses a large needle and syringe to remove the fat globules.

Complications

Lipoma is a benign tumor, which means there is no chance of it spreading to other parts of the body. Therefore, lipomas are not a dangerous disease and rarely cause complications. Lipomas rarely grow back after a surgical procedure, but other lipomas may develop in different parts on your body.

Prevention

The exact cause of lipomas is unknown and the condition is thought to be inherited so there is no definitive way to prevent it yet. You can lower your risk of developing Madelung's disease (a condition that can lead to the growth of lipomas) by limiting the amount of alcohol you drink.

When to see a doctor?

Lipoma is not a life-threatening condition. However, if you have a lump in any part of your body and you are not sure what caused it to grow, then consult a doctor. The doctor will help you in diagnosing this condition and provide appropriate management.

Looking for more information about other diseases? Click here!