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Disseminated superficial actinic porokeratosis
Panta Rouhani1, Max Fischer, Shane Meehan
1The Ronald O. Perelman Department of Dermatology, New York University School of Medicine, USA.
Abstract:
Disseminated superficial actinic porokeratosis, which was described in 1966, is characterized by small, atrophic patches with distinctive keratin rims that occur on sun-exposed areas of the extremities, shoulders, and back. The diagnosis is based on the histopathologic finding of a cornoid lamella, absence of a granular layer, and often a thin epidermis. It is associated with exposure to ultraviolet radiation. Gene studies suggest a pathway defect in which several mutations in keratinocyte proliferation and differentiation lead to development of porokeratosis.
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