Naevus spilus-type congenital melanocytic naevus associated with a novel NRAS codon 61 mutation.

We recently described 17 patients with a new subtype of congenital melanocytic naevi (CMN), designated as "naevus spilus-type CMN" (1). The affected patients present with a large cafe-au-lait (CAL) background macule and dozens of superimposed small and medium-sized CMN. Here we report an additional case with a novel NRAS mutation (Q61L). CMN are categorized by their largest diameter (projected adult size, PAS) (2). Small CMN (SCMN, <1.5 cm PAS) and medium-sized CMN (MCMN, 1.5 - 20 cm PAS) represent rather common, solitary, slightly thickened plaques with prominent terminal hairs. This article is protected by copyright. All rights reserved.