ABSTRACT
Criteria for the clinical diagnosis of early malignant melanomas were sought. A total of 213 pigmented tumors, clinically suspected of being early malignant melanomas, were measured, described, photographed, and classified histologically: 40 proved to be definitely malignant, 49 possibly malignant ("dysplastic"), and 124 definitely benign (mostly melano-/nevocytic nevi, spindle-cell nevi, and Spitz nevi). Malignant melanomas had a horizontal diameter of greater than 5 mm, the patients were older than 18 years, and 62.5% were females. A combination of criteria allowed a clinical diagnosis to be made with an accuracy of 76.2%. The criteria of a horizontal diameter of greater than 5 mm, irregular configuration, and uneven pigmentation permitted 80% of all melanomas to be identified. Histologically atypical, dysplastic nevi could not be diagnosed clinically. They probably constitute a heterogeneous group and only some of them appear to be very early, histologically not clearly recognizable, malignant melanomas.