Immunohistochemical determination of HER-2/neu, c-Kit (CD117), and vascular endothelial growth factor (VEGF) overexpression in malignant melanoma.

PURPOSE: To determine the prevalence and evaluate the possible prognostic value of the molecular targets in malignant melanoma, we studied the overexpression of HER-2/neu, c-Kit, and vascular endothelial growth factor (VEGF) in this patient population. MATERIALS AND METHODS: Overexpression of HER-2/neu, c-Kit, and VEGF was evaluated using immunohistochemical assays in 202 archival tissue specimens. RESULTS: Only two patients (0.9%) revealed HER-2/neu overexpression, whereas 46 (22.8%) revealed c-Kit and 42 (20.8%) specimens showed VEGF overexpression. Multivariate analysis performed did not show a significant difference in survival between c-Kit-positive and c-Kit-negative groups (P = 0.36) and VEGF-positive and VEGF-negative groups (P = 0.25). Interestingly, c-Kit was more likely to be overexpressed in the superficial spreading type and VEGF was overexpressed preferentially in the amelanotic melanoma type. CONCLUSIONS: HER-2/neu has no role in melanogenesis. Both c-Kit (expressed in superficial spreading disease) and VEGF (expressed in amelanotic melanoma) may have significant therapeutic implications as molecular targets, which warrants further investigation.