摘要：The lack of effective therapies for patients with advanced melanoma establishes an early recognition as the aim of clinical and dermoscopic examination, which is the most important factor for improving patient survival and decreases the treatment and management costs. Melanoma in situ is the earliest stage of melanoma. The features of early melanomas, especially in those lesions smaller than 3mm, can be very subtle clinically, dermoscopically and pathohistologically, and it is often impossible to discriminate between a melanoma and nevus. Clinically, de novo melanomas are small brown to black macula with an irregular outline. In melanomas developing in a nevus, there is an asymmetry of the lesion with marked change in color and/or shape of the pre-existing nevus. Dermoscopically, early stages of melanoma show the same global features as thicker melanomas, but in a more subtle way. Asymmetry is the most important parameter; multiple colors are rare. Significant local melanoma-specific criteria, especially when present at the periphery, are irregular pigment network, irregular streaks, and irregular dots/globules, while blue-white structures are rarely found.
