Skip to content
September 27, 2012 / molehunter

A rather odd pigmented lesion

Young person (25-40 age group)  presented with this on the back, friends were worried it had changed.

oddly shaped 8 by 5mm mole. I thought it looked quite like a blue naevus but they are not allowed to suddenly change size or be this shape.

Dermoscopy added very little.

amorphous blue/grey, very irregular outline. Impossible to ignore, photo and observe would have led to sleepless nights.

The global feature is an amorphous blue/grey, rather similar to a blue naevus, but the history and the shape did not fit.  It was excised.

Histology was of a benign dermal naevus with epithelioid and spitzoid features. As I explained to the patient, this is medical jargon for ‘its a really odd looking mole, but harmless’. Excision was I am sure inevitable. I had a feeling it was probably harmless and would have bet £100 on it, but I would not have bet a young person’s life on it. Or an old person’s life.

Dermoscopy can often allow reassurance and avoid surgery, but not always. As far as I am concerned the jury is out on what should be the correct ratio of benign: malignant suspicious pigmented lesions excised. I have heard that it is around 18:1 without dermoscopy and as low as 4: 1 with dermoscopy, but there are 2 things I am certain of from my own experience. One, that dermoscopy often enables us to give confident reassurance and avoid excision. Two, that there is an irreducible minimum number of suspicious looking benign lesions we will have to excise to avoid missing a melanoma.

In the criminal justice system it is often said that it is better to acquit 10 guilty men than to convict one innocent man, with suspicious pigmented lesions it is the other way around-better to excise 10 benign moles than leave 1 melanoma. However, we should strive to avoid procedures and scars when we can. I doubt that this procedure was safely avoidable.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: