Histopathologic Classification of Childhood Craniopharyngioma
Craniopharyngiomas are histologically benign and do not metastasize to remote brain locations or to areas outside the sellar region except by direct extension. They may be invasive, however, and may recur locally. They may be classified as adamantinomatous or squamous papillary, with the former being the predominant form in children. They are typically composed of both a solid portion with an abundance of calcification, and a cystic component which is filled with a dark, oily fluid. Recent evidence suggests that adamantinomatous craniopharyngiomas are locally more aggressive with a significantly higher rate of recurrence compared with the squamous papillary subtype.
The molecular basis for craniopharyngioma differs by histologic subtype. Activating beta-catenin gene mutations are found in virtually all adamantinomatous tumors.[3,4] Conversely, BRAF V600E mutations are observed in nearly all squamous papillary craniopharyngiomas.References
- Karavitaki N, Wass JA: Craniopharyngiomas. Endocrinol Metab Clin North Am 37 (1): 173-93, ix-x, 2008. [PUBMED Abstract]
- Pekmezci M, Louie J, Gupta N, et al.: Clinicopathological characteristics of adamantinomatous and papillary craniopharyngiomas: University of California, San Francisco experience 1985-2005. Neurosurgery 67 (5): 1341-9; discussion 1349, 2010. [PUBMED Abstract]
- Sekine S, Shibata T, Kokubu A, et al.: Craniopharyngiomas of adamantinomatous type harbor beta-catenin gene mutations. Am J Pathol 161 (6): 1997-2001, 2002. [PUBMED Abstract]
- Brastianos PK, Taylor-Weiner A, Manley PE, et al.: Exome sequencing identifies BRAF mutations in papillary craniopharyngiomas. Nat Genet 46 (2): 161-5, 2014. [PUBMED Abstract]