The patient went on to have a biopsy.

Histology

Macroscopic findings: Sellar tumor, a fragment of brownish tissue of 0.3 x 5 cm was received. The entire sample was included.

Final diagnosis: Craniopharyngioma (WHO grade I).

Discussion

This is not a typical case of adamantinomatous craniopharyngioma in that calcification is absent on CT and certainly not typical of a papillary craniopharyngioma (which is usually solid with few water-intensity cyst). A T1 hyperintense masses in the sellar region, the differential diagnosis should include:

• Rathke's cleft cyst (mucoid)
• hemorrhagic pituitary adenoma (late acute/subacute)
• epidermoid/dermoid cysts

Editor note 

Unfortunately, additional diagnostic information is not available and it is uncertain whether this represents an adamantinomatous craniopharyngioma or papillary craniopharyngioma. Given baseline frequency and the dominant cystic component with high T1 signal this most likely represents an adamantinomatous craniopharyngioma.