Correlation of histopathological characteristics with staining patterns in human melanoma assessed by (monoclonal)...

In order to investigate their possible role as prognostic markers, staining with the antibodies NKI/C-3 and anti-S100, that are applicable on paraffin sections, was examined using a group of primary cutaneous melanomas and autologous metastases using the immunoperoxidase procedure. All melanoma lesions stained with anti-S100, and the large majority with NKI/C-3. In primary melanomas showing a moderate or dense associated lymphocytic infiltrate, significantly more tumour cells stained with anti-S100 than in primary melanomas with a slight or absent infiltrate. In markedly pigmented metastases, significantly more tumour cells stained with NKI/C-3 than in less pigmented lesions; in primary melanomas this phenomenon just failed to be significant. In metastases with a high mitotic index a significantly lower proportion of tumour cells stained with NKI/C-3 than in lesions with a low mitotic index. No significant differences in staining were found between a group of primary melanomas with metastases and a group without metastases within a follow-up period of 5 years. Therefore, although staining with NKI/C-3 and anti-S100 appears to be associated with certain histopathological characteristics, it has no direct contribution to the assessment of prognosis in primary melanoma.