Histochemical determinations of copper, zinc, and iron in pigmented nevi and melanoma.

Histochemical determinations of copper, zinc, and iron in intradermal pigmented nevi and melanomas revealed the presence of copper and iron in melanoma but not in nevi. Zinc was not detected in either melanomas or nevi. However, melanin was removed from the tissues prior to staining; therefore, it is possible that zinc was also removed by the procedure. Although the function of copper and iron in the melanoma cell is not known, they may be components of abnormal enzymes.