MUC1 and neoplasm: On immunohistochemical staining, the tumor cells were positive for HMB45 (DAKO, Carpenteria, CA, USA; Figure2B), S100 (DAKO, Carpenteria, CA; Figure2C), and Melan-A (Novocastra, Newcastle-Upon-Tyne, UK; Figure2D), whereas they were negative for cytokeratin (AE1/AE3) and epithelial membrane antigen.