Differentiation of malignant melanoma from benign nevus using a novel genomic microarray with low specimen requirements.

Context.—Histologic examination of clinically suspicious melanocytic lesions is very sensitive and specific for the detection of malignant melanoma. Yet, the malignant potential of a small percentage of melanocytic lesions remains histologically uncertain. Molecular testing offers the potential to detect the genetic alterations that lead to malignant behavior without overt histologic evidence of malignancy. Objective.—To differentiate benign melanocytic nevi from malignant melanoma and to predict the clinical course of melanocytic lesions with ambiguous histology using a novel genomic microarray. Design.—We applied a newly developed single-nucleotide polymorphism genomic microarray to formalin-fixed, paraffin-embedded melanocytic lesions to differentiate benign nevi (n  =  23) from malignant melanoma (n  =  30) and to predict the clinical course of a set of histologically ambiguous melanocytic lesions (n  =  11). Results.—For cases with unambiguous histology, there was excellent sensitivity and specificit...