Craniopharyngioma

Abstract

Definition:

A Histologically benign, partly cystic epithelial tumor of sellar region presumably derived from embryonic remnants of Rathke pouch epithelium, with two clinicopathological variants (adamantinomatous and papillary) that have distinct phenotypes and characteristic mutations.

	Adamantinomatous craniopharyngioma (ACP)	Papillary craniopharyngioma (PCP)
Age	Children and adults	Adults
Location	Suprasellar and sphenoid sinus, cerebellopontine angle	Most frequently suprasellar or third ventricle
Clinical features
Visual disturbances	Present	Present
Hormonal disturbances	• Following are most commonly affected GH> LH/ FSH >ACTH>TSH • Diabetes Insipidus	• Hyperprolactinemia • Personality and mental disturbances • Symptoms of obstructive hydrocephalus
Gross	• Solid + cystic • Cyst contains greenish liquid (motor oil-like)	• Most commonly solid • Cyst fluid is usually absent and clear in nature if rarely present
Microscopy	• ACP has epithelium that grows in cords, lobules, and whorls, with palisading peripheral columnar epithelium and loosely arranged epithelium called stellate reticulum. • “Wet” keratin is a hallmark of this variant.	• PCP has well-differentiated monomorphic columnar/squamous epithelium covering fibrovascular cores with thin capillary blood vessels and scattered immune cells including macrophages and neutrophils. • The epithelium lacks surface maturation and There is no “wet” keratin.
Molecular findings	• Mutations in exon 3 of the gene encoding β-catenin and activation of the WNT pathway	• BRAFV600E mutations suggesting activation of the MAPK pathway

The book chapter illustrates multiple MR images and findings, intraoperative cytology, histopathology, IHC pictures, and their features along with differential diagnosis for each of the above, genetic profile, prognosis, and case studies.