Price, Rywlin, and Ackerman

 
"Summary of Morphological Characteristics of Superficial Spreading Malignant Melanoma Capable of Metastasis
 
I. Poor circumscription of the intraepidermal melanocytic component of the lesion with lateral extension of individual melanocytes.
 
II. Increased number of melanocytes, solitary and in nests, within and above the epidermal basal-cell layer and within adnexal epithelium (Pagetoid appearance).
 
III. Marked variation in size and shape of the melanocytic nests, and confluence of melanocytic nests rather than discrete nests.
 
IV. Absence of maturation of melanocytes with descent into the dermis.
 
V. Melanocytes with nuclear atypia
 
VI. Melanocytes in mitosis
 
VII. Necrosis or degeneration of melanocytes"
 
Price NM, Rywlin AM, Ackerman AB. Histologic criteria for the diagnosis of superficial spreading malignant melanoma: Formulated on the basis of proven metastatic lesions. Cancer 1976; 38:2434–41.
 

Brief Critique

 
Although this constellation of criteria for diagnosis of melanoma by conventional microscopy was an improvement over what had been advanced by authors previously, some important criteria were not included, chief among them asymmetry. Between 1976 and 1999, the criteria forged by Ackerman were honed considerably (see pages 14–15).