DIAGNOSIS OF PIGMENTED LESIONS

Clinically numerous skin lesions have to be differentiated from malign ant melanomas. Most important are the benign melanocytic lesions such as common melanocytic nevi, pigmented spindle cell nevi, Spitz nevi an d blue nevi. From melanocytic lesions also pigmented non-melanocytic s kin lesions have to be separated such as seborrhoic keratoses, pigment ed basal cell carcinomas, verrucae vulgares, dermatofibromas, and vasc ular lesions such as hemangiomas, pyogenic granuloma, angiokeratoma or glomus tumors. Diagnostic accuracy in pigmented skin lesions can be d ramatically improved by dermatoscopy, which is skin surface microscopy al 10x magnification, using a two step procedure. In the first step m elanocytic and non-melanocytic lesions are differentiated by the melan ocytic algorithm. In the second step the malignant potential of the me lanocytic lesions is evaluated by the ABCD rule of dermatoscopy.