Activation of epidermal melanocytes is independent of epithelial proliferation and vascularization. Immunohistologic study using HMB-45 antibody with review of the literature
Lommel, K.; Tronnier, M.; Wolff, H.H.
Der Hautarzt; Zeitschrift für Dermatologie Venerologie und verwandte Gebiete 47(8): 616-623
1996
ISSN/ISBN: 0017-8470 PMID: 8964704 Document Number: 467407
Antibodies against HMB-45 antigen are widely used in the immunohistochemical investigation of melanocytic tumours as a marker of activation. While malignant transformation is one explanation for HMB-45 expression, we searched for other factors by investigating 252 biopsies of non-melanocytic skin lesions with 21 different diagnoses for the presence of HMB-45, using both single and double staining techniques. Epidermal melanocytes in lesions with an increased epithelial proliferation-either neoplastic or reactive-and lesions with a prominent vasculature showed an enhanced expression of HMB-45. The results indicate that the presence of HMB-45 is not only influenced by primary melanocytic changes but also may be dependent on epithelial proliferation and vascular factors. These mechanisms should be considered when interpreting HMB-45 staining of melanocytic lesions.