Management of Nail Unit Melanoma

Fig. 1. Biopsy findings of early nail unit melanoma with Hutchinson sign. (A) A 62-year-old woman presented with irregular black to brownish longitudinal melanonychia with pigment extending to the hyponychium (Hutchinson nail sign). (8) A 6-mm punch biopsy shows the proximal nail fold and cuticle (blue arrow), the nail plate (green arrow), and nail matrix (red arrow) (hematoxylin and eosin [H&E], original magnification x20). The yellow box indicates the window for higher magnification photomicrographs in C and D. (C) Histopathologic findings are subtle, showing only increased pigmentation and melanocytes (H&E, original magnification x100). (D) Melan-A highlights continuous proliferation of melanocytes with prominent dendrites and pagetoid scatter