White Shiny Structures in Melanoma and BCC

Abstract

W HITE SHINY STRUCTURES SEEN UNDER polarized dermoscopy take on 3 distinct morphological appearances. One category includes white shiny lines, which are often orthogonally oriented. This structure also has a metaphoric name known as chrysalis, although some authors believe that chrysalis is a misnomer and prefer that it be replaced with the term crystalline. (We are in agreement with this opinion.) White shiny areas, also known as white shiny clods, appear as larger structureless areas of shiny white color. Finally, rosettes (also a metaphoric term) appear as 4 shiny white points arranged in a pattern reminiscent of a 4-leaf clover. Although both white shiny lines and white shiny areas have been observed in basal cell carcinoma (BCC) and melanoma, the prevalence of these structures seems to differ between these 2 malignant neoplasms. In BCC, we have noticed that it is common to see both white shiny lines (112 of 162 cases [69.1%]) and white shiny areas (39 of 162 cases [24.1%]). In contrast, although we have observed that crystalline structures are prevalent in melanoma (71 of 249 cases [28.5%]), white shiny areas are seen only rarely (8 of 249 cases [3.2%]) (unpublished observation, October 2010). Herein, we show intensely white, widespread, haphazard white shiny lines (Figure, A and C, white arrows) and white shiny areas (Figure, A and C, black arrows) in a superficial BCC (Figure, A and B) and a nodular BCC (Figure, C) under polarized dermoscopy. These structures cannot be seen in the nonpolarized dermoscopic image (Figure, B). We also show white shiny lines in an in situ and invasive melanoma (Figure, D, arrows) and a melanoma metastasis (Figure, E, arrows).