Practical Clues to recognize Melanoma incognito

Introduction & Objectives: To avoid missing melanoma, the current practice is to biopsy all lesions that are suspicious based on clinical and dermoscopic ground. Although most cases of melanoma exhibit clinical clues leading to the correct diagnosis, melanoma can mimic benign melanocytic and non-melanocytic lesions. Confocal microscopy has been shown to increase the diagnostic accuracy for melanoma diagnosis, but little is known about its ability to detect melanoma in the context of lesions that appear dermoscopically benign. Materials & Methods: We present 10 difficult-to-diagnose melanomas, in which additional clues provided by confocal microscopy increased the index of suspicion and prompt us to perform an excisional biopsy. Results: Our cases highlight the following 3 management rules. Confocal microscopy should be used: 1) in newly appearing lesions in high-risk patients; 2) lesions referred by the patient himself as growing lesions even if they are clinically banal 3) Biopsy lesions with unspecific confocal pattern that does not permit to classify the lesion as clear-cut benign. Conclusions: Our case series highlight that melanoma diagnosis is a complex process in which several factors such as patient-related information, clinical history, dermoscopic and confocal features along with “gut” feelings may influence patient’s management. Confocal microscopy in conjunction with dermoscopy can increase the index of suggestion to perform biopsy in difficult-to-diagnose melanomas.