Diagnosis

To diagnose a lipoma, your doctor may perform:

• A physical exam
• A tissue sample removal (biopsy) for lab examination
• An X-ray or other imaging test, such as an MRI or CT scan, if the lipoma is large, has unusual features or appears to be deeper than the fatty

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 biopsy or an MRI or CT scan is typically done if your doctor suspects liposarcoma.