Immunohistochemical Study of MelanocyticDifferentiation Antigens in CutaneousMalignant MelanomaA Comparison of Six Commercial Antibodiesand One Non-commercial Antibody in NodularMelanoma, Superficially Spreading Melanomaand Lentigo Maligna Mel anoma

Overview

In certain primary and metastatic malignant melanomas diagnostic problems may arise due totheir cytologic features and/or absence of synthesis of melanin. As the „classic“ combination ofS-100 protein and HMB-45 may occasionally fail to stain cells of malignant melanoma, we havetested a series of commercially accessible antibodies which were so far not compared by otherauthors in the three most frequent subtypes of this tumor. In surgical specimens from 104 cutaneousmalignant melanomas (40 nodular melanomas, 46 superficially spreading malignant melanomasand 18 lentigo maligna melanomas) the staining intensity and the proportion of neoplasticcells stained with antibodies to S-100 protein, HMB-45, NKI/C3, NKI/beteb, MART 1 (Melan A), KBA62 and Mitf was semiquantitatively analysed. The use of this group of antibodies against melanoma-associated antigens revealed it to be a favourable supplement for the bioptical or cytologicaldiagnosis of malignant melanoma in case the traditional/conventional combination of S-100 proteinand HMB-45 antibody fails. According to the authors’ experience the antibody against KBA 62has shown to be the most effective antibody followed by the antibodies against MART-1 (Melan A)and NKI/C3.

Key words:
malignant melanoma - nodular melanoma - superficially spreading melanoma - lentigomaligna melanoma - immunohistochemistry - differentiation antigens