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A. , Dermal band-like biphasic nevoid/spindle proliferation without junctional activity and nests of epithelioid pigmented melanocytes in superficial dermis

B. , At the periphery, a dermatofibroma-like interstitial pattern, with entrapment of collagen bundle by the spindled component. Congenital-type pattern with intricated melanocytes within the arrector pilores muscle

C. , A band of pigmented epithelioid nests at the top, with scattered melanophages and a dense dermal biphasic proliferation

, Biphasic dermal pattern, with storiform arrangement of the spindle component, islands of nevoid melanocytes and a slight inflammatory response

E. , Atypical case with higher cellularity, involvement of papillary dermis, a slight reticular epiderma hyperplasia, without ulceration. The biphasic pattern is more visible at the bottom and periphery

F. , dense dermal tumor with a bright biphasic pattern, forming well-defined islands of nevoid melanocytes engulfed within an abundant and dense spindled component. Grenz zone is spared and epithelioid pigmented nests are present at the top