It is important to keep an eye on any lumps or bumps that appear on or under the skin, if they are not obviously bruises or other injuries. It is always wise to visit your doctor to check on any lumps or bumps that appear unusual, to rule out more serious conditions (see also our section on skin lesions).
The commonest forms of lumps and bumps are the following three conditions...
Sebaceous cysts
These are non-cancerous lumps often found under the skin on the torso (often the back) or on the head, face or neck. They are formed when a sebaceous gland (which produces an oil called 'sebum' which covers the skin and hair) becomes damaged or blocked and a build up of sebum occurs. This is generally caused by some type of injury - a scratch or even the presence of acne - but the cyst may not be noticed for a while, as they grow very slowly. Some inherited conditions also make people predisposed to sebaceous cysts.
They are generally not painful when they are relatively small, but larger cysts can cause some discomfort. Any cyst that is more than 5cm across, or that is red or painful or discharging pus should be checked by your doctor, as should any cyst that returns after a previous cyst has been removed from the same location.
Cysts are normally surgically removed under a local anaesthetic.
Lipomas
Lipomas are small fatty 'lumps' under the surface of the skin, often found on the arms, shoulders, thighs, stomach, neck or back. They feel soft to the touch and are painless and can often be 'moved around' under the skin. They are classified as 'benign' growths, that is, not harmful.
People aged 40-60 seem to be most prone to developing lipomas and they are also tend to run in families.
Despite the fact that they are harmless, it is always a good idea to have any new lump or bump checked by your doctor to rule out any other more serious condition.
Lipomas can be removed with surgery or liposuction. Another treatment option is steroid injection, but this does not completely remove the lipoma, only reduce it in size.
Ganglions
A ganglion is a form of non-cancerous lump that forms on a tendon, most often a tendon in the hands, but sometimes on the feet, knees or ankles. The ganglion contains fluid and it is not fully understood why they form, although they may be linked to a response to injury or overuse of the tendon. Women aged 20-40 seem to be more prone to them.
30%-50% of ganglions disappear without treatment, but it is still a good idea to have any lump or bump checked out by your doctor.
In the olden days, the preferred treatment was 'Bible therapy' i.e. dropping a heavy book on the ganglion, but this is not recommended today. If they are not causing any discomfort or muscle weakness they may not need treatment, although 'needle aspiration', where the fluid is drained through a fine needle, is one option, as is surgery to remove the ganglion.