A clonal proliferation of abnormal keratinocytes characterized by the development of localized or multiple atrophic skin patches surrounded by an annular keratotic ring called cornoid lamella.

A heritable disorder of faulty keratinization characterized by the proliferation of abnormal clones of KERATINOCYTES and lesions showing varying atrophic patches surrounded by an elevated, keratotic border. These keratotic lesions can progress to overt cutaneous neoplasm. Several clinical variants are recognized, including porokeratosis of Mibelli, linear porokeratosis, disseminated superficial actinic porokeratosis, palmoplantar porokeratosis, and punctate porokeratosis.

Porokeratosis is a clonal disorder of keratinization characterized by one or more atrophic patches surrounded by a clinically and histologically distinctive hyperkeratotic ridgelike border called the cornoid lamella. Multiple clinical variants of porokeratosis are recognized.