Written for parents and young people (key stage 2 and above)
What are the aims of this leaflet?
The aim of this leaflet is to give children more information about their pilomatricoma.
What is a pilomatricoma?
A pilomatricoma is a lump under the surface of the skin.
A pilomatricoma is not a cancer (it will not spread to other parts of your body) and is not caused by an infection (you will not spread it to other people).
Pilomatricomas are made from hair cells. If the lump has been there for a long time, then it can be hard (as calcium, the chemical that makes bones hard and strong, collects in it).
Mostly these lumps are on the head or neck, but they can be on other parts of your body. They more often occur in young children and girls get them more often than boys.
They are not very common, and they are harmless.
Most children only have one, but you can make more than one.
A pilomatricoma can also be called other names including pilomatrixoma, trichomatricoma or a ‘calcifying epithelioma of Malherbe’.
Why have I got a pilomatricoma?
The hair cells, in the lump only, have an alteration which means extra protein is produced in the lump
Is a pilomatricoma inherited?
It is very rare for more than one person in a family to have a pilomatricoma. Sometimes if more than one person in a family has these lumps, doctors do special tests called genetic tests to try to find out why.
What does a pilomatricoma look and feel like?
They can be skin coloured or pink, purple or brown with white areas within them (due to calcium). They can feel firm or hard. They can have a regular or irregular shape. They are usually smaller than 3 cm. Usually, they are not painful or itchy. Sometimes they can burst and a white or yellow chalky material can come out of them.
There is nothing you could have done to stop the lump from coming but, to prevent it becoming inflamed or infected, you should not pick or squeeze it.
If the lump becomes red or sore it may be inflamed or infected and you would need to see your doctor.
How will pilomatricoma be diagnosed?
Generally, skin doctors can tell by looking and feeling these lumps what they are. Sometimes they will ask you to have a scan. This will usually be an ultrasound scan. This does not hurt and uses a special camera touching your skin with some gel on it. This allows the lump to be seen more clearly.
The doctors will know for certain that it is a pilomatricoma when it is removed and looked at under the microscope.
Why treat Pilomatricoma?
A pilomatricoma will usually not go away on their own. Most children and families choose to have the lump removed as it is often on the face or neck. When it is on the arm, for example, then you may choose to keep it.
How is pilomatricoma treated
The only way to remove the pilomatricoma is to cut it out (called an excision). This is a small operation. The doctors can either numb the skin, whilst you are awake [local anaesthetic] or you can be put to sleep [general anaesthetic]
Once it is fully removed it is unlikely to come back.
When is the treatment carried out?
As the lumps are harmless, there is no rush to remove them.
You can choose to keep your lump.
Many families wait until the removal can be done without a general anaesthetic.
Doctors will only advise early removal if they are not sure that the lump is a pilomaticoma and want to get the lump analysed under a microscope .
What can you expect?
If you choose to have the lump removed under local anaesthetic, the skin around the lump may sting for a few seconds before it goes numb.
Removing the lump will create a small scar – this will fade over time and not be so noticeable as you get older.
The scar will be red or darker in colour for a few months but should become nearer to the same colour as the rest of your skin with time, although in some people it can be either paler or darker than the skin.
Where can I get further information?
Web links to detailed leaflets:
J Pediatr Surgery 2013 48 1551 Characterizing pilomatricomas in children : a single institution experience.
Links to patient support groups:
There are no specific patient support groups for this condition
This leaflet aims to provide accurate information about the subject and is a consensus of the views held by representatives of the British Society for Paediatric Dermatology (BSPD): individual patient circumstances may differ, which might alter both the advice and course of therapy given to you by your doctor.
This leaflet has been assessed for readability by the BSPD Young people and British Association of Dermatologists’ Patient Information Lay Review Panel
BRITISH ASSOCIATION OF DERMATOLOGISTS
PATIENT INFORMATION LEAFLET
PRODUCED NOVEMBER 2021
REVIEW DATE NOVEMBER 2024