Acanthosis nigricans nævoïde ou « RAVEN » (rounded and velvety epidermal nevus) : trois cas

The striking clinical features of this rash rule out confusion with any other epidermal nevus (because of age of onset, shape and texture) or with acanthosis nigricans (because of its topography and the lack of associated neoplastic or endocrine disease). A dozen similar case reports can be found in the medical literature, mostly under the term “nevoid acanthosis nigricans”. Such a rash may be linked to postzygotic mosaicism with the same mutations of the FGFR3 gene. However, since the physiopathology of this rash remains hypothetical, we propose to name it “RAVEN”, for “rounded and velvety epidermal nevus”, which is simply a descriptive acronym and nothing more.