Difficulties in the diagnosis of spitzoid melanocytic lesions

Abstract

Spitz nevus was first described in 1948 by Dr Sophie Spitz, who termed it juvenile melanoma based on its striking cytologic resemblance to melanoma, being composed of large epithelioid and spindle cells, and its prevalence among children. Several changes in terminology have since occurred with increased knowledge and experience, particularly regarding its occurrence in adult populations and rather indolent clinical behavior. Nevertheless, the distinction of Spitz nevus from melanoma still remains a significant problem in dermatopathology. Most classic examples of Spitz nevi can be easily distinguished histopathologically from melanoma, although lesions with unusual or atypical features still pose diagnostic difficulties, particularly in small or partial samples. In general, poor interobserver diagnostic concordance is not uncommon. Herein, we review the histopathological features of Spitz nevi, including common and recently reported variants, and spitzoid melanoma, and discuss recent advances in ancillary studies that may prove useful in their diagnosis. © 2010 Expert Reviews Ltd.