The magnetic resonance imaging of the brain revealed a large heterogeneous solid-cystic mass in the left temporal lobe with no connection to the craniopharyngeal duct, the suprasellar, or intrasellar regions, although there was no significant edema or mass effect (Figure 1).
A primary ectopic craniopharyngioma is a rare tumor that diagnoses for the first time without any Rathke's pouch within the vestigial craniopharyngeal duct. Secondary ectopic craniopharyngiomas are rare event.
According to the embryogenetic theory, the adamantinomatous subtype arises from epithelial remnants of the craniopharyngeal duct, which connects the stomodeal ectoderm with the evaginated Rathke's pouch, which in turn forms the adenohypophysis.
They were named by Harvey Cushing and described as being derived from "epithelial rests ascribable to an imperfect closure of the hypophysial or craniopharyngeal duct
".1 Since this early description by Cushing, the treatment strategies for these tumours have undergone significant advancement.
Benign teratomas arising from the midline nasal septum have been well described and resected endoscopically [4,7]; however, a skull base teratoma on a neurovascular stalk arising from the craniopharyngeal duct, superimposed on a KFS background, presents a singular challenge.
The tumor stalk was felt to represent a patent/persistent craniopharyngeal duct, and multiple other midline intracranial abnormalities including corpus callosum dysgenesis, midline lipoma, and dysmorphic hypothalamic and brainstem changes were also noted (not shown).
Here, we report a striking case of a female patient with KFS with a longstanding, pendant skull base teratoma extending through a patent craniopharyngeal duct leading to obstruction of the nasopharynx and worsening headaches.
It is supposed to develop owing to transformation of embryonic squamous cell structures along the path of the craniopharyngeal duct
. It shows the bimodial presentation with higher incidence in children than adults.
In 1904, Erdheim postulated that craniopharyngiomas developed from squamous remnants of the obliterated craniopharyngeal duct
, suggesting that these tumors may arise at any point along the tract of migration of Rathke's pouch from the vomer, the roof of the nasopharynx, or through the midline sphenoid bone beneath the floor of the sella turcica.
Craniopharyngiomas are suprasellar tumours that are believed to arise from craniopharyngeal duct
remnants.(1) These tumours are common and represent 50% of all suprasellar tumours in childhood, with a peak incidence between the ages of 8 and 12 years and a second, smaller, peak in middle-aged adults.(2) The tumours are typically lobulated, cystic masses with a mural nodule.(2) The cystic component is often the predominant portion and occurs in over 90% of cases.(3) The fluid content of the tumour is usually thick and yellow, and can be reminiscent of engine oil on gross pathology.(2)