PMEL and neoplasm: Immunohistochemistry supported the diagnosis, with tumor cells staining positively for S100, HMB45, Melan A, and P16 (Figure 4C), and negatively for Desmin, CD99, AE1/3, Cam5.2, CK7, Chromogranin, Calretinin, CD56, CD45, P63, and Synaptophysin.