Papular Epidermal Nevus with “Skyline” Basal Cell Layer (PENS) Following a Blaschko Linear Pattern

Abstract

Papular epidermal nevus with "skyline" basal cell layer (PENS), a variant of epidermal nevi, has recently been described as a small, round or polygonal papule, visible at birth or shortly thereafter, with characteristic histopathologic features. It has been considered a separate entity from keratinocytic nevi because no lesion observed thus far has followed any of the known archetypical mosaic patterns. Here we describe for the first time a PENS lesion following a linear distribution pattern along Blaschko's lines.

Papular Epidermal Nevus with Skyline Basal Cell Layer (PENS): Three New Cases and Review of the Literature

“…Five of these developed lesions soon after birth, and in the three remaining cases, the exact age at appearance of the lesions was not mentioned. The number of lesions was variable (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). Eight patients (42%) had extracutaneous findings, mainly mild developmental or psychomotor delay.…”

Syndrome PENS (papular epidermal nevus with “skyline” basal cell layer)

“…L'association de cet hamartome à des anomalies neurologiques a permis d'autonomiser le syndrome PENS comme un nouveau syndrome neuro-cutané [2][3][4]. Nous rapportons une observation originale de syndrome PENS, où les hamartomes épidermiques sont associés à des troubles sévères du spectre autistique (TSA).…”

“…L'hamartome PENS se caractérise par de petites plaques centimétriques en nombre variable (1 à 18), siégeant avec prédilection sur les membres, parfois sur le tronc, le visage ou le cou. La disposition des plaques est presque constamment éparse et non systématisée, une seule observation d'hamartome PENS disposée suivant les lignes de Blaschko ayant été décrite [4]. Les lésions élémentaires sont des papules de 1 à 7 mm coalescentes, à surface plane et rugueuse, de couleur blanchâtre à brune.…”

Papular Epidermal Nevus with “Skyline” Basal Cell Layer Syndrome – Natural Course: Case Report and Literature Review

“…Palms and feet were spared. The cutaneous aberrations did not follow any specific pattern such as Blaschko lines as indicated in another case [ 3 ]. The invisibility of the migrations of embryonic cells is a normal condition and separates itself from genetic skin disorders such as focal dermal hypoplasia [ 4 ].…”