Lipoma

What is lipoma?

Lipomas (or lipomata) are the most common benign soft-tissue tumor mainly composing of benign fatty cells. Lipomas are benign, slow-growing, fatty tumors forming soft, lobulated masses enclosed by a thin fibrous capsule. Lipomas rarely undergo malignant / cancerous change, forming liposarcoma.

Cause

It may be associated with obesity or minor genetic mutation.

Symptoms

Lipomas present as soft masses below the skin, and they usually situate in the subcutaneous plane between the skin and muscle. The skin above the lipomas are usually normal. Lipomas does not cause pain, but it will slowly grow. Lipomas are soft round or oval or lobulated shaped mass with characteristic of being easily deformed, sliding slightly below the skin, and not attached to the overlying skin or muscle. A characteristic "slippage sign" may be elicited by gently sliding a finger tangentially towards the edge of the lipoma. The lipoma will be felt slipping under and away from the finger. Lipomas usually will not cause inflammation, infection, abscess or skin necrosis. However, Large lipoma may compress surrounding tissue, such as causing subcutaneous fat atrophy or muscle atrophy.

Treatment

Indications for lipomas surgery are:

• Cosmetic reasons
• Symptomatic
• Large size (e.g >5cm)
• Suspicious of malignancy, particularly when liposarcomas is suspected

Complete surgical excision with the capsule is essential to prevent local recurrence, Lipomas can be lobulated, and it is essential that all lobules be removed. Otherwise, local recurrance can happen. Traditional lipoma excision surgery involves an incision slightly larger than the lipoma, excision of the the lipoma, and wound closure with several interrupted sutures.

Currently, minimal invasive surgery (MIS)/ minimal access surgery (MAS) are indicated for all subcutaneous lipomas. MIS / MAS involve using the smallest incision along the low skin tension line over the lipoma. The lipoma is shelled out from the tiny incision. After excision of the lipoma, the wound is closed below the skin with absorbable sutures and there is no need to take off any sutures.

MIS / MAS can be performed with the placement of videoscope and instruments at a distance from the lipoma. The lipoma is seperated from surrounding tissue and removed. Bleeding is controlled. Then the wound is closed with absorbable sutures subcutaneously and there is no need to take off sutures.

Liposuction is an MIS / MAS that allows removal of the lipomas through very small incisions, the locations of the incision wound can be remote from the actual lipomas. As there is a small chance of residual fat cell from the lipoma leaving behind after liposuction, there are only few doctors performing liposuction for lipomas.

Modern MIS / MAS allow the incision to be placed in an inconspicuous location. For example, axillary incisions may be used to remove lipomas from the back or the chest.

Frequently Asked Questions

Q: Is lipoma a cancer?
A: No. Nearly all of the lipomas are benign. Liposacroma happens raraly and it is a kind of cancer.

Q: Is it necessary to remove all lipomas?
A:  No. You should consider surgery if you have lipomas with the following indications for surgery: poor cosmesis, symptomatic, >5cm size, or suspicious of cancer.

Q: How to differentiate lipomas from sebaceous cysts?
A: They can be differentiate by their skin attachment and presence of slippage sign.