Polygons

 Polygons  - Angulated shapes due to flattened rete ridges with melanocytic proliferation and grey dots of melanin in melanophages and free in the dermis. They are a fgeature of lentiginous melanomas in chronically sun damaged skin particularly on the upper back and shoulders.

Melanoma in situ 

Lentiginous melanoma

LPLK 

Pigmented Solar Keratosis

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