Dermoscopic structures	Schematic illustration	Definition	Histopathologic correlation
Pigment network		Grid-like network consisting of pigmented lines and hypopigmented holes	Melanin in keratinocytes or melanocytes along the dermoepidermal junction
			Network lines correspond to the rete ridges
			Holes correspond to the suprapapillary plate
Pseudonetwork		Diffuse pigmentation interrupted by adnexal opening	Pigment in the epidermis or dermis in which the rete ridges are attenuated
		Usually seen in facial lesions
Negative pigment network		Serpiginous interconnecting hypopigmented lines that surround irregularly shaped pigmented structures resembling elongated curvilinear globules	Remains unknown
			Presumed to be related to bridging of rete ridges or large melanocytic nests in the papillary dermis, resulting in compression of adjacent rete ridges; these nests may correspond to globules that are not spherical in shape
Aggregated globules		More than three clustered, well- demarcated, round to oval, symmetric structures, or three or more of these structures aligned at the lesion's perimeter	Nests of melanocytes at the dermoepidermal junction
		May be brown, black, or blue
		Diameters are greater than 0.1 mm
Dots		Small, round structures of less than 0.1 mm in diameter	Aggregates of melanocytes or melanin granules
		May be black, brown, or blue-gray
Streaks (pseudopods and radial streaming)		Streaks are radial projections at the periphery of the lesion, extending from the tumor toward the surrounding normal skin; may be brown or black	Confluent junctional nests of melanocytes
		Pseudopods are streaks with finger-like projections with small knobs at the tips
		Radial streaming is streaks without knobs at the tips
Peppering (or granularity)		Tiny, blue-gray granules	Melanin deposited as intracellular (mostly within melanophages) or extracellular particles in the upper dermis
Structureless areas		Devoid of dermoscopic structures within the lesion and without manife sting any regression structures	Relative decreased concentration of melanin or flattening of rete ridges
		Tend to be tan to light brown, but have lighter pigment compared with the rest of the lesion
Peripheral light brown or tan structureless areas		Structureless areas (as above), located at the periphery of the lesion	Partial or complete flattening of the rete ridges
			Increased number of pigmented atypical melanocytes predominantly at the dermoepidermal junction
			Diffuse scattering of melanocytes in the spinous layer of the epidermis
Blotches		Dark brown to black homogeneous areas of pigment that obscure visualization of any other structures	Aggregates of melanin in the stratum corneum or throughout all layers of the skin
Regression structures		Include scar-like depigmentation (lighter than the surrounding uninvolved normal skin; appear shiny white under polarized dermoscopy) often combined with peppering; combination of scar-like depigmentation and peppering gives the appearance of a blue-white veil	Scar-like changes/white areas: thickened fibrotic papillary dermis
			Blue areas: correlate with melanosis type of regression
Blue-white veil		Confluent blue pigmentation with an overlying white ground-glass haze	Aggregation of heavily pigmented melanocytes or melanophages in combination with compact orthokeratosis of the stratum corneum
White shiny structures (more conspicuous with polarized dermoscopy)		Rosettes: appear as four white shiny points creating a pattern reminiscent of a four- leaf clover A4	Histopathologic correlation has not been fully explained
		Crystalline structures: short, white, shiny linear streaks that are often parallel or orthogonal to each other A5, A6	Altered collagen or fibrosis in the dermis
		White shiny areas: appear as larger structureless areas of shiny white color	Altered stromal matrix
Parallel pigment pattern		On volar skin (i.e., palms and soles)	Pigmented melanocytes in the furrows (crista limitants) or ridges (crista intermedia) on skin of palms and soles
		Parallel rows of pigmentation following the furrows (as seen in nevi) or ridges (as seen in melanoma) of the dermatoglyphics