a 36-year - old man presented with sudden severe occipital headache , and neck stiffness in may 1999 . after several weeks , the headache subsided , however , blurred vision subsequently developed .
t1-weighted ( 665/14/2 [ repetition time / echo time / excitation ] ) and t2-weighted ( 4200/99/2 ) mr images showed a large cystic mass with a small solid portion in the left temporal lobe ( figs .
gd - dtpa enhanced t1-weighted images showed marked enhancement of a thick peripheral wall and solid portion ( fig .
1c ) . on diffusion - weighted mr images ( b value=1000 sec / mm , isotropic image ) ,
the mass was surgically excised , and histopathologic examination revealed a typical adamantinous craniopharyngioma with anastomosing epithelial islands and a palisaded layer of cells , as well as an area of keratinization and numerous calcifications ( fig .
craniopharyngiomas are generally considered to be epithelial tumors arising from remnants of the craniopharyngeal duct , which connects the stomodeal ectoderm with the evaginated rathke 's pouch , which in turn forms the adenohypophysis ( 7 , 8) .
this theory suggests that craniopharyngiomas can arise anywhere along the migration of rathke 's pouch , which extends from the vomer and the roof of the nasopharynx , through the midline sphenoid bone to the floor of the sella turcica .
thus , craniopharyngiomas can potentially arise in unusual locations such as the nasopharynx ( 2 , 8) , sphenoid bone ( 9 ) , third ventricle ( 3 ) , and posterior fossa ( 10 ) .
however , the above hypothesis does not explain the development of craniopharyngiomas either in the pineal gland ( 5 ) or the temporal lobe as in our case .
there is no clear embryological reason for craniopharyngiomas to originate from the pineal gland or temporal lobe .
( 6 ) suggested that they might originate from totipotential or multipotential cells that reside in the pineal gland .
however , metastasis has never been described in this benign neoplasm , and therefore we think that the former hypothesis is more reasonable than the latter .
craniopharyngioma would not usually be included in the differential diagnosis of a temporal lobe mass .
given the well - defined cystic mass with peripheral dense enhancement , our preoperative diagnosis was pilocytic astrocytoma .
craniopharyngiomas can be classified into two histopathologically and clinically distinct subtypes ( i.e. adamantinous and squamous - papillary variants ) ( 8) .
the adamantinous type consists of a predominantly cystic lobulated tumor , which is often observed in an intrasellar / suprasellar location in children .
these cysts contain various amounts of cholesterol , triglycerides , methemoglobin , protein , desquamated epithelium , and watery fluid content .
squamous - papillary craniopharyngioma , on the other hand , consists of a predominantly solid or mixed solid - cystic spherical tumor in a suprasellar location in adults .
the solid tumor parts have an inhomogeneous but intense enhancement with small necrotic areas , and calcifications are rare .
the combination of papillary and adamantinous tumor parts within the same neoplasm has been described in 15% of these tumors . in summary , although our case did not show any specific radiologic finding permitting the differentiation of craniopharyngioma , to the best of our knowledge , this is the first case of a craniopharyngioma originating in the temporal lobe .
it does not appear to be embryologically derived from ectopic embryonic remnants of the craniopharyngeal duct .
 herein , we report on an unusual case of craniopharyngioma arising in the temporal lobe with no prior history of surgery and with no connection to the craniopharyngeal duct . 
 mr images showed a cystic tumor with a small solid portion . to the best of our knowledge , 
 this is the first case of a craniopharyngioma occurring in the temporal lobe . 