Figure 1.

Histopathology of craniopharyngiomas. (A) Adamantinomatous craniopharyngioma. Epithelial nests with peripheral palisading columnar epithelium (arrowhead), nodular whorls (yellow dotted circle), stellate reticulum (asterisk), and aggregates of ‘wet’ keratin (black arrow) (Hematoxylin Phloxine Saffron (HPS) staining, ×200); (B) Adamantinomatous craniopharyngioma. Nucleocytoplasmic translocation and accumulation of β-catenin are detected by immunohistochemistry, especially in the nodular whorls (brown nuclear immunopositivity, yellow dotted circle, ×200); (C) Papillary craniopharyngioma. Papillae are composed of fibrovascular cores covered by a well-differentiated non-keratinizing squamous epithelium (HPS, ×100); (D) Papillary craniopharyngioma. Detection of BRAF V600E mutation by immunohistochemistry is positive (red cytoplasmic immunopositivity in squamous neoplastic cells, ×200).