Virtual Medical Centre

Skin Biopsy

• What is a skin biopsy?
• Why do a skin biopsy?
• Shave biopsy

What is a skin biopsy? 

A skin biopsy is basically a very small sample of skin that is removed by a doctor so that it can be examined in a lab to determine what cells it is made up of.

Skin lesions (lumps, bumps and other changes) are very common things for a person to present to their GP with. While many of these are harmless, they can be cosmetically displeasing and many have the potential (however unlikely) to develop into something more serious. As such, all skin lesions should be investigated or removed if the general practitioner has concerns about it.

For many skin lesions, such as skin cancers, the first treatment is surgical removal. This is because it does not only provide a definitive diagnosis, but is also the most effective treatment. For some lesions however, it is necessary to take a small sample of the tissue before proceeding with treatment. The name for these 'small samples' is a biopsy, and so a skin biopsy is just a small sample of skin that is removed and sent to a lab for further analysis.

Why do a skin biopsy?

A skin biopsy may be done because the treatment will be very different depending on what the lesion turns out to be, or it may be that the doctor has to be very sure it is worth removing, such as if removal would require extensive surgery on a sensitive area such as the face.

The information that can be obtained from a skin biopsy would include things such as what type of tumour or problem is within the lesion, what types of cells make up the lesion and how they look, as well as confirming that all of a tumour has been removed.

Shave biopsy

A shave biopsy is a technique where the very surface layer of skin is 'shaved' off by using the blade of a scalpel. It does not get a very deep sample of tissue, and so may not be the right technique for some skin cancers that go deeper into the tissue. However, it is very useful for taking samples from large areas, where tumours are present in a few different sites or have borders that aren't very clear.

Some people say that a shave biopsy should be done with caution on pigmented (coloured) lesions. This is because if the lesion comes back as being a melanoma then the shave biopsy can cause some trouble with finding out further information about the lesion. While some people hold to this belief, others say that a shave biopsy can be a very useful tool in pigmented lesions.

A shave biopsy will consist of the following steps:

1. Firstly, the area will have a small amount of local anaesthetic injected into it to numb it.
2. The actual removal of the lesion can be done in a few different ways:
   • Very sharp special scissors can be used to remove the lesion.
   • A scalpel blade held along the surface of the skin can be used to remove the lesion.
   • A razor blade can be slightly bent, with the sharp edge running underneath the lesion to remove it.
3. If there is any bleeding, then diathermy (where an electrically charged piece of metal creates a very minor burn) or a substance called 'ferrous sulphate' can be used.

Generally, a shave biopsy will heal very well, with little bleeding and usually no scarring. In fact, it can heal so well that sometime a doctor will have to note down or photograph the area as it will be impossible to tell where it was taken from by the time the results come back!