Brain Pathology Case of the Month - May 2017

Contributed by Tara Jayde Nail MD1, Julio M Araque MD2 , John Vender MD3 , Amyn M Rojiani MD, PhD1
Departments of Pathology1, Radiology2 and Neurosurgery3, Medical College of Georgia, Augusta University, Augusta GA


A 57 y/o female presented with sudden onset of transient right homonymous hemianopsia while driving. Later the same day she also reported a 3-4 hour period of decreased cognitive ability, being unable to perform calculations. She was seen in the emergency room and underwent neuroimaging studies. MRI demonstrated a 25.9 x 23.6 x 21.3 mm round, slightly lobulated, mass within the suprasellar cistern with significant mass effect. A preoperative T1-weighted sagittal image without contrast showed a suprasellar mass, isointense to the brain cortex with compression and superior displacement of the optic chiasm and floor of the third ventricle (Fig. 1a). The inferior margin of the mass was in contact with the dorsum sella and posterior aspect of the diaphragm sella. No intrasellar extension was seen. The posterior margin extended into the region of interpeduncular cistern with associated splaying of the cerebral peduncle. T1-weighted gadolinium-enhanced sagittal images demonstrated homogenous enhancement. Normal pituitary gland is seen within the sella turcica, independent of the lesion. There is no enlargement of the sella turcica (Fig. 1b) T2-weighted coronal image shows low signal intensity of the mass (Fig. 1c). The patient underwent a right fronto-temporo-parietal stereotactic craniotomy for resection of the lesion.


Smear preparations reveal large epithelioid cells with generous cytoplasm which had a distinctly granular appearance (Figs. 1d, 1e). The nuclei were round and fairly uniform, often eccentrically placed, with a prominent nucleolus and dispersed chromatin. On routine histologic sections the specimen was moderately cellular with thin walled vessels (Fig. 1f). The granular cytoplasmic content was readily evident (Fig. 1g). No significant pleomorphism was seen and mitotic activity and necrosis were absent. Tumor cells displayed patchy but consistent immunoreactivity for S-100 (Fig. 1h), with focal mild positivity for Inhibin and CD68. TTF-1 immunoreactivity was strong and readily seen in the vast majority of tumor cells (Fig. 1i). What is your diagnosis?


International Society of Neuropathology