Lipoma
Lipomas are the most common cause for a lump under the skin. They may be single although some people make multiple lipomas particularly on their arms although they may occur anywhere in the body. Frequently they are quite small measuring up to an inch (2cm) in size although they can grow to be very large. Typically they cause few symptoms but they can be quite tender even painful. A condition where there are lots of painful lipomas is called Dercum's disease. Malignant tumours of fat, called liposarcomas, are very rare. Benign lipomas do not become cancerous (i.e.do not turn into liposarcomas). If a lump is confidently diagnosed as a lipoma there is no need for it to be removed if it is not painful or growing. If it is causing symptoms or there is doubt about the diagnosis then surgical removal is usually advisable.
Sebaceous Cysts
The most common cyst of the skin is the epidermal cyst or sebaceous cyst. These are benign lumps containing dead skin cells.
Fat Necrosis
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