Morphologic and immunohistochemical features of breast nevi

A large number of publications recognize that there are melanocytic lesions with microscopic features similar to melanoma, related to their location. Those locations are represented by the ear, the milk lines (axillary, breast, periumbilical and inguinal regions), palms, soles, and flexural regions. Starting from Rongioletti F et al. study in 2004, we measured 10 histological parameters on 96 nevi (39 from the breast) and notes with 0 if absent or impossible to evaluate and with 1 if present. The score for each lesion ranged from 0 to 7 and we compared the features of the breast nevi with the nevi from the control sites and found that breast nevi present more atypical features than the nevi from the other sites (absence of demarcation of melanocytes at lateral margins, nests and dyscohesive pattern and melanocytic atypia). We also performed immunohistochemical examination on lesions that presented three or more of the examined histological parameters, but the results were nor suggestive. The conclusion of this study is that the atypical features of the breast nevi are only site related atypias and have no hormonal influences.