[Prognosis and invasion marker expression of cutaneous melanoma. Metastasis-associated genes (nm23, CD44v3, MMP2].

For the evaluation of the prognosis of the melanoma malignum (MM) several markers have been used before but none of them was powerful enough therefore a search for new markers is justified. The authors have studied the expression of three metastasis associated proteins, nm23, CD44v3 and MMP2 collagenase using immunohistochemistry on the paraffin embedded tissue samples of 22 primary skin melanomas. The expression of these markers was independent from the thickness of the tumor or the clinical stage of the disease. Due to the frequent discrepancy between the thickness of the tumor and the actual outcome of the disease, they regrouped the cases according to the biological behaviour of the tumor into non-metastatic, lymph node-metastatic and organ metastatic forms. Based on the MMP2 expression +/- tumors can be found but the expression does not correspond to the biological behaviour of MM while decreased nm23 expression characterized the lymph node metastatic tumors. CD44v3 expression was rare in MM and occurred at low level, however, when expressed it showed significant correlation to the organ metastatic phenotype. The authors concluded that the classic invasion markers in case of MM have a limited potential in the characterisation of the invasive phenotype, therefore more sensitive markers are necessary.