Holzle, Kind, Plewig, and Burgdorf

 
"All malignant melanomas initially are malignant melanoma in situ, since abnormal melanocytes almost always begin to proliferate in the epidermis. As both patients and physicians have become more skilled in the early recognition of malignant melanomas, there has been a shift towards the identification of malignant melanoma in situ. While it is impossible to clinically diagnose malignant melanoma in situ, it is a reassuring histological diagnosis after a suspicious pigmented lesion has been excised.
 
Malignant melanoma in situ presents as a macular, relatively uniform colored lesion. Once again, the most useful way to remember the features is the ABCD rule. Changes in the superficial skin markings and regression or development of a nodular component are suggestive of invasive malignant melanoma." (Fig. 10)
 
Holzle E, Kind P, Plewig G, Burgdorf W. Malignant Melanoma Diagnosis and Differential Diagnosis. New York: Schattauer, 1993:92.

View Figure  		Fig. 10  Our diagnosis and comment: Melanoma versus Clark's nevus. As the legend rightly states, a diagnosis of melanoma or Clark's nevus in the lesion shown here can be made by surety only by examination of sections of tissue from a biopsy specimen taken of it, preferably one that is by excision in toto with a narrow margin. The vast majority of Clark's nevi do not resemble melanoma clinically; most look like the small pigmented papule on the far right of this photograph. In brief, so-called funny looking moles, atypical moles, and nevi with architectural atypia are an exceptional presentation clinically of Clark's nevi. For practical purposes, all brown macules and slightly elevated papules on the trunk and proximal extremities that are benign are Clark's nevi.
 

Brief critique

 
Holzle, Kind, Plewig, and Burgdorf declare that "it is impossible to clinically diagnose malignant melanoma in situ," but that statement is untrue. A flat lesion of melanoma is in situ, the abnormal melanocytes there being confined to epidermal and adnexal epithelium. If it is possible to diagnose melanoma when it is elevated, as surely is the case, it is possible equally to diagnose melanoma when it is flat and in situ. It is the macular stage that is most important in regard to being rid forever of melanoma; a flat lesion of melanoma devoid of signs of regression is curable by simple excision. Curiously, in contradistinction to their earlier statement, Holzle et al. advise that "malignant melanoma in situ presents as a macular, relatively uniform colored lesion." Melanoma in situ presents itself as a macule, but not always as one that is relatively uniform in color. Although that may be the case in some instances, the lesion more often is somewhat varied, mostly in shades of brown. Despite having stated that a macule of melanoma in situ is "relatively uniform" in color, the co-authors then go on to promote the mnemonic of the "ABCD rule" in which C stands for Color variability! They state rightly, however, that alteration of skin markings, signs of regression, and development of a nodule are indicative of melanoma that no longer is in situ.