An osteoid osteoma is a small, noncancerous tumor of the bones. It often affects leg bones or the spine but can affect any bone. They are usually found in young people. Many osteoid osteomas disappear on their own, but some may require surgery for removal.
A lipoma is a soft movable lump of fat under the skin. They are usually harmless, but it’s important to know what they feel like to rule out other causes of lumps.
A fibroadenoma is a benign (non-cancerous) breast tumor from overgrown cells forming a mass. It is the most common kind of breast tumor in young women.