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Diseases and Conditions
Special to CNN.com
A lipoma is a slow-growing, fatty tumor situated between the skin and the muscle layer. Often a lipoma is easy to identify because it moves readily with slight finger pressure. It's doughy to touch and usually not tender. You could have several that persist for years. Lipomas can occur at any age, but they're most often detected in middle age.
A lipoma isn't cancer and is usually harmless. Treatment generally isn't necessary, but if the lipoma is in a bothersome location, is painful or is growing, it should be removed.
Signs and symptoms
A lipoma is a flattened lump located just under the skin. It feels soft and doughy and moves easily with slight finger pressure. Lipomas often occur in the neck, shoulders, back, arms and thighs.
Most often, lipomas remain small — less than 5 centimeters in diameter — but they can grow large, reaching more than 20 centimeters across. Lipomas can be painful if they grow and press on nearby nerves. Because it grows slowly, you might have a lipoma for years before you notice it.
The exact cause of lipomas isn't clear. Sometimes lipomas are detected after an injury. But it's uncertain whether they're caused by the trauma or whether their detection was just incidental. Lipomas also tend to run in families, so genetic factors likely play a role in their development.
When to seek medical advice
A lipoma is rarely a serious medical condition. But if you notice a lump or swelling anywhere on your body, it's best to have it checked by your doctor.
Screening and diagnosis
A doctor can make a diagnosis by physical examination of the lump. If there's any doubt, your doctor may do other tests, such as a biopsy or removal of tissue.
There's a very small chance that a lump resembling a lipoma may actually be a form of cancer called liposarcoma. Liposarcomas — cancerous tumors in fatty tissues — grow rapidly, don't move under the skin and are usually painful. A needle biopsy or a CT scan is typically done if your doctor suspects liposarcoma.
If you have a lipoma, no treatment is usually necessary. However, if the lipoma is in a bothersome location, is painful or is growing, your doctor might recommend that it be removed. Treatments include:
January 11, 2006