Figure 5. Photomicrographs of resected left frontotemporal tumor of the woman with pituitary carcinoma in 2021. (A) Hematoxylin-eosin stained low-power view shows the tumor comprising of sheets of polygonal cells with eosinophilic granular cytoplasm. (B) Hematoxylin-eosin-stained high-power view shows moderate nuclear atypia and increased mitotic activity of the tumor cells. (C) Immunohistochemical Ki67 staining demonstrates 10% elevation of the index, indicating mitotic activity of the tumor cells.