White lines

White lines represent collagen in the dermis. They are seen in BCCs but also in some thicker nodular melanomas particularly the amelanotic kind and the peculiar desmoplastic variant.They are best seen using a polarising dermatoscope where you see best deeper into the lesion. The white lines usually have to be broad to make them significant of melanoma.

 White lines reticular usually indicate fibroplasia of the papillary dermis, a finding that may be found in early melanoma and in so called "dysplastic nevi" (Clark nevus). This is the same as the term negative network seen in some melanomas.