Primary melanoma. A, Ulcerated polypoid tumor from the neck of a 73-year-old man. B, IHC for Sox10: the tumor cells are homogenously immunoreactive for Sox10. C, IHC for PRAME: the tumor cells diffusely express PRAME. D, Melanoma is present in both the epidermis and dermis (H&E-stained section). E, IHC for PRAME highlights both in situ and invasive tumor cells.