Updates on molecular diagnostic assays in melanocytic pathology.

Melanoma is the leading cause of death among cutaneous neoplasms. For the great majority of melanocytic tumors histopathologic examination can reliably distinguish nevi from melanomas; however, there is a subset of melanocytic neoplasms that defy an accurate diagnosis using histopathological criteria alone. For such tumors, additional ancillary tests would be beneficial in adjudicating a more definitive diagnosis. Conventional ancillary studies such as immunohistochemistry have only a limited utility in distinguishing an atypical nevus from melanoma. In recent years few molecular ancillary tests have been developed to help guide the diagnosis of ambiguous melanocytic proliferations. These tests are based either on the identification of genomic copy number changes or on the differential expression pattern of selected genes in nevi and melanomas. This review will present an updated overview of the major ancillary tests used in clinical practice for the diagnosis of challenging melanocytic neoplasms. [ABSTRACT FROM AUTHOR]