case_images: PMC3843908_01
case_images: a A reddish-brown dome-shaped hyperkeratotic nodule on the left lower leg. b The lesion showed a whitish scaly area, pinkish-white structureless areas, a few milia-like cysts, dotted and glomerular vessels, light brown globules, and dotted hemorrhages on dermoscopy.
case_images: cde-0005-0304-g01.jpg
case_images: PMC3843908_01_cde-0005-0304-g01.jpg
case_images: F1
case_images: Physical examination revealed a reddish-brown dome-shaped hyperkeratotic nodule of 11 x 10 mm with a sharply demarcated, symmetrical border (fig. 1a). Dermoscopic examination demonstrated prominent whitish scaly areas of ring-like appearance, pinkish-white structureless areas, a few milia-like cysts, dotted and glomerular vessels, light brown globules, and dotted hemorrhages (fig. 1b).
case_images: a Panoramic view revealed a well-circumscribed symmetric lesion with hyperkeratosis, acanthosis, and pseudohorn cysts. b The lesion was composed of spindle-shaped and epithelioid melanocytes with large cytoplasm arranged in confluent nests with peripheral clefts. c There was stromal fibrosis surrounding the nests. d At the papillary layer, proliferation of capillary could be found. HE.
case_images: cde-0005-0304-g02.jpg
case_images: PMC3843908_01_cde-0005-0304-g02.jpg
case_images: F2
case_images: Hyperkeratosis, acanthosis, and pseudohorn cysts were observed (fig. 2a). There were confluent nests with peripheral clefts composed of spindle-shaped and epithelioid melanocytes with large cytoplasm at the dermal-epidermal junction and in the papillary dermis (fig. 2b). There was stromal fibrosis surrounding the nests (fig. 2c). Moderate proliferation of capillaries in the papillary dermis was observed (fig. 2d).
case_images: a Melan-A staining showed weaker findings in the deeply situated cells than in the superficial cells. b Nests were partly ascending into the stratum corneum. Melan-A staining.
case_images: cde-0005-0304-g03.jpg
case_images: PMC3843908_01_cde-0005-0304-g03.jpg
case_images: F3
case_images: Melan-A was weaker in the deeply situated cells than in the superficial ones (fig. 3a), and nests ascending up to the stratum corneum appeared as transepidermal elimination (fig. 3b).