Variegated Dermoscopy of in situ Melanoma

Abstract

Background: Melanomas in situ (MIS) are difficult to diagnose, lacking well-established dermoscopic descriptors. Objective: The aim of this study was toimprove the identification of early melanomas describing the variegated dermoscopic features of MIS and their correlation with demographic and clinical aspects. Methods: Dermoscopic images of 114 histologically proven MIS were evaluated by 3 expert dermoscopists and classified into their main dermoscopic patterns. Dermoscopic features were also considered for their correlation with clinical parameters. Results: Eight different dermoscopic subtypes of MIS were identified: reticular grey-blue (27.2%), reticular (21.1%), multicomponent (20.2%), island (10.5%), spitzoid (7%), inverse network (6.1%), ‘net-blue globules’ (5.3%) and globular (2.6%). Clinical characteristics of lesions and patients varied according to the different dermoscopic groups. Conclusion: We hypothesize that the different dermoscopic subgroups of MIS correspond to lesions with a different origin and, possibly, various patterns of growth and a different biological behaviour.

Management Rules to Detect Melanoma

“…This was highlighted in a recent study describing eight novel dermoscopic patterns of in situ melanoma. The authors postulated that the morphologic diversity might reflect a variability in origin or biologic behavior of the tumor [15]. Some of the traditional algorithms have been accordingly modified to a lower threshold for excision of lesions showing only one of the classic criteria that, if prominent, may be judged enough to warrant excision [16].…”

Negative Pigment Network Identifies a Peculiar Melanoma Subtype and Represents a Clue to Melanoma Diagnosis: A Dermoscopic Study of 401 Melanomas

“…globular-homogeneous and multicomponent (when reticular, globular, and homogeneous areas were all found within the same lesion) (12,13). Other patterns observed in our study were the starburst pattern (attritjuted to lesions with a radial aspect), the reticular grey-blue regression pattern (coarse blue-grey net, with thick grey-blue lines and large holes, corresponding to white or pink regression areas) (10,11) and the aspeeific pattern, when none of the previous main patterns could be identified.…”

“…Several descriptors characterizing in situ and thin MMs have been proposed by the current study group, such as the dermoscopic island (9), reticular grey-blue regression (10,11) and peculiar network atypias (12). Moreover, classification into different melanoma subtypes enables the recognition of MM subpopulations that may not be immediately recognizable according to the established main dermoscopic patterns (7,13).…”

“…The dermoscopic parameter "negative pigment network" (NPN), introduced by Menzies et al in 1996 (14), consists of relatively light areas making up the "cords" of the network, and darker areas filling the holes; it is seen as a negative ofthe pigmented network and was also named reticular depigmentation (15) or inverse network (13). Its presence has been noticed in MMs, acquired and congenital naevi.…”

Melanoma in situ

“…Of these, the reticular grey-blue is the most common. 77 Other studies have also suggested various dermoscopic features that may be helpful in distinguishing MIS from other pigmented lesions.…”