Abstract

Histological assessment of melanocytic naevi constitutes a substantial proportion of a dermatopathologist’s daily workload. Although they may be excised for cosmetic reasons, most lesions encountered are clinically atypical and are biopsied or excised to exclude melanoma. Although dysplastic naevi are most often encountered, cytological atypia may be a feature of several other melanocytic lesions, including genital type naevi, acral naevi, recurrent naevi, and neonatal or childhood naevi. With greater emphasis being given to cosmetic results, and because of an ever increasing workload, several “quicker and less traumatising” techniques have been introduced in the treatment and diagnosis of atypical naevi including punch, shave, and scoop shave biopsies. A major limitation to all of these alternatives is that often only part of the lesion is available for histological assessment and therefore all too frequently the pathologist’s report includes a recommendation for complete excision so that the residual lesion can be studied. Complete or large excision of all clinically atypical naevi permits histological assessment of the entire lesion, and in most cases spares the patient the need for further surgical intervention.