In very general terms there are four different surgical approaches to removing and / or examining skin lesions:
- Excision (including 'wide area excision' or 'wide local excision' and 're-excision).
- Biopsy.
- Flap repair.
- Mohs technique.
Excision
This is where a skin lesion is surgically removed using a surgical blade (scalpel). It is necessary to remove not only the affected section of skin, but also a segment of healthy skin tissue around the lesion itself. This is referred to as a 'margin', and ensures that all abnormal cells are removed, even those that may be present, but not visible, in the margin around the lesion. The larger the lesion itself, generally the larger the margin of healthy tissue that needs to be removed. This type of excision is also referred to as a 'wide local excision' or 'WLE'. A re-excision is where an excision biopsy has already been taken in the same area (see biopsy).
Biopsy
A biopsy is a procedure to remove a section of skin so that it can be analysed for the presence of abnormal or cancerous cells. There are three approaches to taking a biopsy of the skin:
- Excision (as above).
- Punch - this is where a small circle of skin is removed.
- Shave - this is where only a very thin layer of the top section of the skin is removed.
Flap repair
In cases where the section of skin needing to be removed is too large to be able to join the remaining skin on either side, a 'flap repair' may be needed. In this procedure, a section of skin very close to the site of the removed section is also removed and used in the site where the skin was removed. The advantage of flap repairs over other types of skin graft is that the skin retains its natural appearance, and recovery from the surgery is quicker as the original blood supply remains in place.
Mohs technique
Also known as Mohs surgery, this is a relatively new procedure often used where the risk of abnormal or cancerous cells regrowing is deemed to be high or where sections of skin needing to be removed are on the fingers or near the eyes or ears. Mohs surgery involves removing incredibly thin sections from the surface of the lesion and having these sections immediately analysed for the presence of abnormal cells. This is continued until a section of lesion is examined which is completely clear of abnormal cells. Due to the need for real time analysis, this approach takes more time than conventional techniques and is not performed by Dr Janine Arnold.