Craniopharyngioma causes
Craniopharyngioma causes
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Marjan Khan M.B.B.S.[2]
Overview
The cause of craniopharyngioma has not been identified.
Causes
- Craniopharyngioma is a nonglial intracranial tumor derived from a malformation of embryonic tissue.
- There are differing hypotheses on its embryonic origin.
- The caause of craniopharygioma is although not completely understood.
- Some authorities advocate that it originates from ectodermal remnants of Rathke's pouch.
- Few pathologists believe that it originates from residual embryonal epithelium of the anterior pituitary gland and of the anterior infundibulum.
Embryonic theory
- According to this theory Craniopharyniomas arise from neoplastic transformation of embryonic squamous cell nests of Rathke's pouch with the stomodeum.
- During the process of proliferation and rotation of the cells of Rathke's pouch leading to the formation of the adenohypophysis, cell remnants of the craniopharyngeal *duct are spread through the intrasellar and suprasellar region.
- The rotation of the adenohypophysis is caused by different rates of cellular multiplication, resulting in a spread of cells of the craniopharyngeal duct to the suprasellar region.
- The rare location at the cerebellopontine angle could fit with this hypothesis.
Metaplastic theory
- Papillary craniopharyngiomas are the result of metaplasia of the adenohypophyseal cells in the anterior pituitary, resulting in the formation of squamous cell nests.
- This theory is supported by the presence of metaplastic nests in the gland
Genetics
- Multiple chromosomal abnormalities have been reported by classic cytogenetic analysis.
- Most tumors had abnormalities involving chromosomes 2 and 12.
- More than 70% of adamantinomatous craniopharyngiomas harbor a mutation of the β-catenin gene.
- Most of the mutations affect exon 3, which encodes the degradation targeting box of β-catenin compatible with an accumulation of nuclear β-catenin protein.
- In a few cases of adamantinomatous craniopharyngioma, the same β-catenin mutations occurring in the epithelial cells have been identified in mesenchymal cells.
- No mutations have been demonstrated in papillary craniopharyngioma.