Two Congenital Cases of Pigmented Epithelioid Melanocytoma Studied by Fluorescent in situ Hybridization for Melanocytic Tumors: Case Reports and Review of These Recent Topics

Dermatology, Robert-Debré Hospital, APHP, Paris V - Descartes University, France.
Dermatology (Impact Factor: 1.69). 01/2010; 221(2):97-106. DOI: 10.1159/000314160
Source: PubMed

ABSTRACT The term 'pigmented epithelioid melanocytoma' (PEM) has recently been proposed as a nosological framework grouping lesions formerly known as animal-type melanomas, sporadic epithelioid blue nevi and Carney complex-associated epithelioid blue nevi. Congenital PEMs have been reported extremely rarely and their prognosis is poorly known. Four-color fluorescent in situ hybridization (FISH) for melanocytic lesions is a recent method developed to assess the malignant potential of ambiguous melanocytic lesions. Here we describe 2 cases of congenital epithelioid and strongly pigmented melanocytic lesions consistent with PEM. No BRAF gene mutation was found in the 2 cases. FISH for melanocytic lesions was also performed. The first case proved entirely negative, whereas the second one showed a positive zone with an extra copy of chromosome 6. The prognosis and management of PEM are discussed, with a review of the available data on the history, demographics, molecular alterations and histopathological aspects of this entity. PEM seems to represent a unique low-grade melanocytic tumor with a limited potential of metastasis to lymph nodes, but a favorable long-term clinical course. The published data about FISH for melanocytic tumors, and especially PEM, are reviewed. Four-color FISH may be a useful tool to assess more accurately the prognosis of these tumors.

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