An ugly duckling

A 26-year-old woman consulted for many moles. One of them was considered "an ugly duckling".

Dermoscopy revealed:

• an irregular blotch
• asymmetry of form
• chrysalis-like structures

Pathology revealed a superficial spreading melanoma (SSM) with a Breslow index at 0,6mm

Chrysalis structures

A 51-year-old patient consulted for this lesion located on his back.

Dermoscopy revealed :

• arborizing vessels
• ulcerations
• chrysalis structures

This lesion was a basal cell carcinoma.

Crystalline or chrysalis structures are white shiny streaks that can only be seen with polarized dermatoscopes.

Crystaline or chrysalis structures are most commonly observed in basal cell carcinoma and invasive melanomas and rarely seen in nevi. In melanoma,they reflect increased tumor thickness and progression. 
The significance of crystalline/chrysalis structures in the diagnosis of melanocytic and nonmelanocytic lesions. Y. Balagula, R.P. Braun, H. S. Rabinovitz et al.  J Am Acad Dermatol 2012;67:194.e1-8.