[Recognition and follow-up of the atypical naevus: benign marker or precursor of melanoma?].

Dysplastic (atypical) naevi have long been subject to discussion with regard to their nature; even their existence has been doubted. Recently, the atypical naevus has been formally identified by molecular genetic characteristics as an intermediate lesion between banal naevi and melanoma. However, the atypical naevus, as long as it is stable and asymptomatic, is regarded as a benign lesion that does not warrant excision. Atypical naevi can occur in families in which melanoma is prevalent, and those patients need to be included in regular surveillance by a dermatologist. Two male 30-year-old patients who presented with atypical naevi in different contexts are used as illustrations in this clinical lesson.