The patient went on to have a resection.
Histology:
The section shows a single small fragment of tissue. This is composed of irregularly shaped islands of mature squamous epithelium which are dispersed in a loose fibrous stroma. These show strong immunostaining for cytokeratins AE1/AE3 and CAM5.2. The stroma contains aggregates of keratin. Focal foreign-body type granulomatous inflammation in association with some collections of keratin are noted. There is also focal dystrophic calcification. No cyst formation is seen. The features are those of a craniopharyngioma.