[Clinical value of a dermatoscopic classification of Clark nevi]

The aim of this study was to evaluate the practical value of the dermatoscopic classification of Clark nevi

Dermatoscopic images of 268 lesions clinically and dermatoscopically diagnosed as Clark nevi were presented to 2 dermatologists without knowledge of the histological diagnosis. The dermatologists evaluated the lesions according to a simplified version of the classification scheme for Clark nevi proposed by Hofmann-Wellenhof and differentiated between 12 different types of Clark nevi.

The most common type of Clark nevus was the reticular-homogenous type (n = 64, 23.9%), followed by the globular-homogeneous type (n = 32, 12%) and by the homogenous type (n = 30, 11.2%). The overall inter-rater agreement between the examiners was moderate to good (kappa = 0.58). The highest level of agreement was found for the peripheral hyperpigmented type (kappa = 0.83). Histologically, 17 lesions (6.3%) were diagnosed as melanomas. The frequency of melanoma was highest among the peripheral-hyperpigmented type for one observer and among the homogenous type for the other observer. No melanoma was found among the globular, reticular-globular, and the central-hyperpigmented types.

A dermatoscopic classification of Clark nevi is practically feasible and allows--to some extent--a risk stratification of Clark nevi, which could be useful for clinical management.