Figure 2. Postoperative examinations: (A) Macroscopically, a tumor of size 45×25 mm with a black surface was detected in the posterior vaginal wall (yellow arrows). (B) Hematoxylin and eosin ×4; and (C) Hematoxylin and eosin ×40. Microscopically, the tumor cells were arranged in sheets and nests and exhibited nuclear pleomorphism, an eosinophilic cytoplasm, brisk mitotic activity, and melanin production. Immunohistochemically, the tumor was positive for (D) SOX10 and (E) the Ki-67 labeling index was 70%.