Wayte

 
" . . . the microscopic diagnosis [of melanoma] is based on the following features. A. Junctional changes . . . B. Intradermal invasion . . . C. Loss of stromal relationship . . . D. Lack of maturation . . . E. Mitotic activity . . . F. Melanogenesis . . . G. Surface ulceration . . . . The following features seen on microscopic examination are of very little value. A. Epidermal invasion . . . B. Dermal inflammatory reaction . . . C. Epithelial hyperplasia . . . D. Junctional 'activity.'" (Fig. 6) Wayte DM. Pathology of nevi and melanomas. In: Helwig EB, Mostofi FK. The skin by 30 authors. Maryland: Williams and Wilkins, 1971:522–24.

View Figure  		Fig. 6   Our diagnosis and comment: Melanoma in situ. The findings pictured are neither those of a "freckle" of any kind nor of "precancerous melanosis." The changes fulfill criteria for melanoma within the epidermis (melanoma in situ).
 

Brief Critique

 
Only lack of maturation of abnormal melanocytes with progressive descent into the dermis is a solid criterion for distinguishing melanomas from melanocytic nevi of various kinds, but that finding is not met with consistently in melanomas. All of the other criteria stated by Wayte to be characteristic of melanoma may be seen in Spitz's nevi.