Presentation
None provided.
Patient Data
MRI of the brain and pituitary demonstrates a sizable mass centered in the suprasellar and interpeduncular sellar, continuous with the infundibulum of the pituitary gland. It is isointense on T1 and iso- to perhaps slightly hyperintense on T2 weighted images. It enhances vividly. Normal pituitary tissue is seen in the bass of the fossa.
The patient went on to have a biopsy.
Histology
MACROSCOPIC DESCRIPTION: A fragment of cream / grey-tan tissue, approximately 4 x 3 x 2 mm. (1.1) frozen section tissue.
MICROSCOPIC DESCRIPTION: The tumor consists of nests and strands of cells within a collagenous fibrous stroma. The tumor cells are generally polygonal in shape but in places they become elongate. In these areas a fascicular architecture with focal whorling is present. Cytoplasm ranges from minimal to moderate amounts of amphophilic material. The nuclei are rounded or somewhat elongate, with finely speckled chromatin. Sometimes small nucleoli are apparent. There is no tumor necrosis and mitotic figures are infrequent. Immunohistochemical stains show no staining for pituitary hormones, cytokeratins or epithelial membrane antigen. No convincing staining for chromogranin or synaptophysin is found. There is, however, strong nuclear and cytoplasmic staining for S100 with no staining for gp-100 or melan-A.
FINAL DIAGNOSIS: The morphologic and immunohistochemical features are in keeping with the rare entity of pituicytoma 1.
Case Discussion
This case demonstrates appearances of a rare pituitary / infundibular tumor, a pituicytoma. This patient has been followed up for many years with little growth.