SURFACE MICROSCOPY OF NEVI AND MELANOMAS - CLUES TO MELANOMA

In this present study, 260 histologically confirmed melanocytic skin t umours (188 benign naevi and 72 malignant melanomas; from 1989 to 1990 ) were investigated with regard to valid surface microscopical criteri a of malignancy. The tumours were analysed using a system which assess ed eight components. Most melanomas were characterized by the followin g pattern: asymmetrical pigment distribution, more than three colours, black pigment, peripheral stripes, and asymmetrical depigmentation. T he results were evaluated statistically by contingency tables and logi stic regression procedures. On the basis of the classification derived , the sensitivity and specificity were determined for lesions from 199 1, and were 0.9 and 0.85, respectively. Many melanocytic naevi were no t identified by the above criteria, or were found only occasionally. P igment network was often absent in naevi and melanomas, and was not de cisive for the diagnosis. The present investigation demonstrates that in vivo diagnosis of pigmented melanocytic lesions can be improved by surface microscopy.