Ask Dr. H | Lumps called lipomas are benign

Question:

I have several fatty tumors just above my waistline. They range from the size of a marble to the size of a walnut. My doctor looked at them and called them "lipomas." He said they were benign and don't need removal unless they get bigger or painful. What caused them?

Answer:

Lipomas are common and very much benign. They're soft, rubbery masses within the layer of fat just under the skin. They most often develop on the beltline, back, arms and legs. We aren't sure what causes lipomas. One theory is that perhaps a bump or bruise to the fatty tissue irritated the fat cells and stimulated a tumor to form. Lipomas do seem to run in families. Despite being a fatty tumor, they are not necessarily associated with obesity, and losing weight won't affect them.

If a lipoma has been present for a number of years without change, the odds are overwhelming that it's benign. A lipoma feels soft, rubbery and freely movable within surrounding tissue. An experienced doctor can easily diagnose it by touch. Lipomas generally are painless; they may hurt slightly when pressed (due to surrounding nerves and blood vessels).

Could it be cancerous, like a small "liposarcoma"? If the lipoma continues to grow, or popped up rapidly, then removal and biopsy might be worth considering - just to be sure. Still, a doctor experienced at examining the skin can fairly easily tell the difference between one or more benign lipomas and something more serious.

As for treatment, unless the lipoma is painful, interferes with movement or is cosmetically unattractive, I recommend leaving it alone. If you wish to have your lipoma removed, or are concerned that the tumor may be cancerous, there are two main procedures: simple surgical removal under local anesthesia, or liposuction.

One more thing: If you have more than one lipoma, you will likely develop new ones as the years go by.