Integrating clinical/dermatoscopic findings and fluorescence in situ hybridization in diagnosing melanocytic neoplasms with less than definitive histopathologic features

Abstract

Background: Early diagnosis of melanoma remains of paramount importance, because it has been widely demonstrated that survival is strongly related to Breslow thickness. Several studies have shown that dermatoscopy improves accuracy in the diagnosis of melanoma. Although histopathology is considered the gold standard to differentiate melanoma from nevi, there are some cases of melanoma in which the histopathologic features are less than definitive. It has also been demonstrated that fluorescence in situ hybridization can be used to differentiate melanomas from nevi based on chromosomal copy number aberrations.

Objective: In this study we present a case series to demonstrate the value of combining fluorescence in situ hybridization and dermatoscopy/clinical history to enhance diagnostic capability for selected cases of early melanoma.

Methods: Cases were identified that had dermatoscopic findings or clinical history highly suggestive of melanoma and fluorescence in situ hybridization evaluation positive for melanoma, but histopathologic features that were less than definitive. Two dermatopathologists performed independent histologic analysis of specimens and two dermatologists experienced in dermatoscopy reviewed dermatoscopic and clinical data.

Results: Nine cases meeting inclusion criteria were identified. In 6 cases the histologic differential diagnosis was dysplastic nevus versus early melanoma whereas in 3 cases the differential diagnosis included Spitz nevus versus early melanoma.

Limitations: Limitations of this study include restrictive inclusion criteria and study design restricted to a case series.

Conclusion: This exploratory study demonstrates that in a subset of early melanoma cases, combining multiple diagnostic modalities such as dermatoscopy and molecular techniques with histology enhances detection of early melanoma.