ABSTRACT
Compared to pigmented skin tumors, non-pigmented lesions have less dermatoscopic clues to a specific diagnosis. In contrast to pigmented lesions the diagnosis of non-pigmented lesions, lacking the clues of melanin structures, is more challenging. A study has shown that in raised non-pigmented lesions, surface keratin, dermatoscopic white structureless areas, and dermatoscopic white circles are more robust than vessel pattern analysis as diagnostic clues. The clue of “white lines” has not been formally evaluated in non-pigmented lesions, but the current authors rate it as an important clue and have incorporated it into their algorithmic method. There are two types of white lines which can be present in both pigmented and non-pigmented lesions. First, there are white lines that may be seen with any dermatoscope and then there are “perpendicular white lines” that are only seen with polarizing dermatoscopes.
