Help understanding Dysplastic Nevus

A couple of questions stand out – first about your melanoma in situ.  You say it was excised with clear margins.  Were additional margins taken?  You really want AT LEAST 5mm of clear margins.  One study I read actually suggested better outcomes with 8-9mm margins. 

Second, dysplastic nevi.  Typically they are characterized as mildly dysplastic, moderate or severe.  These are not considered  cancer.  But either the architecture of the mole and/or some of the cells have atypical features.  Not bad enough to say they are cancerous but still not totally "normal".  In general, depending on the classification, you want either clean margins to 5mm for these lesions.  There isn't a standard rule for them all but severely atypical lesions usually are taken with 5mm margins.  The others you would like at least clean margins to possibly 2-3mm.  Different docs have different strategies.  The best bet would to have a biopsy that removed the entire lesion, if possible, so nothing is left behind.  The excision is called a WLE – wide local excision.  And yes, that is what they should be doing for this lesion – and hopefully what they did for the melanoma in situ.

My husband has also had a couple dysplastic nevi biopsied, one came back classified as moderately atypical and one severely atypical. Essentially, the derm referred to them as "funny moles." For the severely atypical one, they removed cleaner margins around that one, but left the moderate one as is for now. The derm explained that while they are benign, those that are classified as "severe" have cells that could potentially turn into cancer. In other words, they aren't "normal" cells, but ones that could misbehave in the future, especially in those with a history of melanoma.