A lipoma is a non-cancerous growth that shows up on or under the skin, made up of fat cells. It feels soft and rubbery and can appear anywhere on your body, typically without causing pain. They are the most common abnormal growth that healthcare providers come across. About 1% of people will have a lipoma at some point, but they might be more common because they often go unnoticed due to their small size.
Usually, lipomas don’t need any treatment unless you want them removed. Surgery is an option, along with steroid shots and liposuction. Doctors classify them based on their location and appearance under a microscope. Most lipomas grow just under the skin, but they can also develop deeper in soft tissues, including muscles. These deeper lipomas can become quite large before they’re ever noticed. Researchers are working on tests to distinguish between different types of lipomas and to rule out cancer.
Lipomas are generally round or oval, with fat cells clumped together in lobes, all contained by a fibrous capsule. Most don’t cause symptoms, though a soft, lumpy area can be felt or seen under the skin. Usually, they grow slowly and can be moved slightly when touched. They can occur anywhere on your body and in many organs. About 5% of people with lipomas will have more than one. They appear most often in certain areas but usually stay the same size and are not painful. However, they can press on nearby tissues like nerves or blood vessels, which might cause discomfort.
The exact cause of lipomas isn’t well understood. There’s no strong evidence linking them to chemical or radiation exposure. Some lipomas might be genetic, but factors like gender and ethnic background don’t seem to play a role. Researchers are continuing to study general risk factors to understand who might be more likely to develop them. Anyone can get a lipoma, but they’re more common in adults between the ages of 40 and 60. Sometimes, they can appear after an injury to the area.
You would typically identify a lipoma with a primary care provider. They can often determine if it’s a lipoma just by looking at and feeling the lump, checking its size, consistency, and movement. A biopsy is needed for confirmation, which involves taking a small tissue sample to look at under a microscope. If you notice a new or unusual lump, it’s essential to see a healthcare provider because some serious conditions can mimic lipomas. Sometimes, additional lab tests and imaging might be necessary if the initial biopsy results are unclear.
Lipomas usually don’t need treatment unless they grow quickly, cause pain, or for cosmetic reasons. They’re most often treated by dermatologists, general surgeons, or plastic surgeons. Removing the entire capsule of the lipoma lowers the chances of it growing back, especially for those just under the skin because they don’t attach to connective tissue. If you’re thinking about removal, it’s a good idea to ask your provider about the risks and benefits of the procedure and what to expect afterward. Generally, once a lipoma is fully removed, it’s considered “cured” and unlikely to return. There’s no proven way to prevent lipomas or slow their growth. Most people seek treatment mainly for cosmetic reasons, especially if the lipoma is in a visible spot. Excision is the most common treatment, but other options include liposuction and corticosteroid injections. Researchers continue to study lipomas to better understand their causes and the best way to treat them. If you notice a large growth or experience discomfort, contact a healthcare provider. Lipomas are usually not cancerous, but other tumors can look similar and might need different treatments.
