Bilateral nasal obstruction due to an intranasal craniopharyngioma

Sagittal view of an embryo showing Rathke's pouch in green, an epithelial diverticulum that arises during the fourth week of gestation from the oral stomodeum and invaginates superiorly towards the brain while diencephalic neuroectoderm descends. Cooperatively the two will form the pituitary gland. Inset B: Rathke's pouch eventually forms the anterior lobe and pars intermedia of the pituitary gland (shown in green). Incomplete resolution of the craniopharyngeal duct can result in cellular rests, which can give rise to purely infrasellar craniopharyngiomas. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of the article.)

(A) Endoscopic view prior to excision of the right nasal cavity. (B) Coronal T1-weighted MRI.

Hematoxylin and Eosin slide, 20×: the tumor is composed of broad strands of squamous epithelium with peripheral palisading of the nuclei resting on a basement membrane, giving it a cyst like configuration. The “cysts” appear to be filled with an amorphous, eosinophilic, acellular material. There is abundant compact “wet keratin” and some areas that appear to be calcified. These features are consistent with an adamantinomatous craniopharyngioma.