Embryonal craniopharyngioma. Case report of the morphogenesis of a craniopharyngioma.

Abstract

Ordinary craniopharyngiomas affecting sellar regions of children and preadolescents are composed of ameloblastomatous and/or squamous constituents. The authors encountered an autopsy case of a stillborn infant with a large craniopharyngioma with unusual manifestations. The craniopharyngioma was analyzed using detailed histologic and immunohistochemical techniques. An autopsy revealed a large tumor arising from the pituitary gland with associated severe hydrocephalus. Histologically, the cells of the tumor showed features of ameloblastoma and organoid structures simulating tooth buds and adenohypophyseal primordia in the stage of organogenesis. Cells of the latter were shown to be immunoreactive for chromogranin A and six adenohypophyseal hormones. Because embryology of the adenohypophysis and the teeth indicated that all of the epithelia in this tumor emerged during the normal development of the stomodeum, it was believed that an "embryonal form of craniopharyngioma" would characterize this organoid neoplasm best. The possible morphogenesis of craniopharyngioma is also discussed.