"Granular cell tumours of the pituitary are composed of sheets of densely packed large polyhedral cells, with abundant eosinophilic cytoplasm filled with periodic acid-Schiff–positive granules 1,2,4."
"The occurrence of calcification may be influenced by the size of the lesion5."
"Some cases exhibit heterogeneous enhancement with contrast, others demonstrate a homogeneous enhancement pattern5."
"Care must be taken when reading older literature as granular cell tumours of the pituitary region, and alternative names including pituitary choristoma and Abrikossoff tumour, have in the past been thought to be, at least by some, equivalent to a pituicytoma."
"In the 5th edition (2021) of the WHO classification of CNS tumours, these tumours are grouped with pituicytomas and spindle cell oncocytomas of the pituitary gland as "most likely representing a spectrum of a single nosological entity" unified by all having expression of thyroid transcription factor 1 (TTF-1) 4. Having said that, distinctive histological features are described, and as such, these two other entities are discussed separately."
"GFAP: usually negative"