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Medline ® Abstract for Reference 84

of 'Atypical (dysplastic) nevi'

Persistent melanocytic nevi: a review and analysis of 205 cases.
Sommer LL, Barcia SM, Clarke LE, Helm KF
J Cutan Pathol. 2011 Jun;38(6):503-7. Epub 2011 Mar 1.
BACKGROUND: Melanocytic nevi can recur or persist if not completely excised and are capable of mimicking malignant melanoma, both clinically and histologically.
OBJECTIVE: To characterize the impact of anatomic site, biopsy method, size, margin involvement and type of original melanocytic nevus on recurrence/persistence of melanocytic nevi. Secondarily, we sought to determine if the original type of melanocytic nevus could be determined solely from microscopic examination of the recurrent/persistent nevus.
METHODS: One hundred and eighty-five patients with 205 persistent nevi were identified. Of these, 108 cases had original biopsy specimens available for review. Location, original biopsy size, biopsy method, margins and interval to recurrence were recorded for each. A group of 232 non-persistent nevi was established as a control population.
RESULTS: There was a female predominance in persistent nevi with the back being the most common site for persistence. Dysplastic melanocytic nevi were the most likely to persist. Accurate determinationof the original type of melanocytic nevus from microscopic examination of the persistent nevus was possible in only 67% of the cases.
CONCLUSION: Clinicians should take larger and deeper biopsies of clinically dysplastic and conventional melanocytic nevi on the back to prevent recurrences. Grading atypia of the persistent melanocytic nevi is unreliable.
Temple University School of Medicine, Philadelphia, PA, USA.