Presentation
3 months of amenorrhea.
Patient Data
T1 isointense pituitary mass mildly expands the sella and bulges into the suprasellar cistern, elevating the midline infundibular but not contacting or compressing optic chiasm. There is no evidence of cavernous sinus invasion. T2 signal is heterogeneous, with a ovoid fluid signal non-enhancing portion anteroinferiorly measuring 12 x 7 x 13 mm, while the remainder of the mass contains small heterogeneous T2 signal with mild diffuse enhancement. A 4 mm non-enhancing cystic component appears to extend along the infundibulum.
A few small T2 hyperintense white matter lesions are in excess of expected for age.
However The remainder of the imaged brain (please note this study has been targeted to the pituitary, and as such the whole brain has not been imaged) appears unremarkable.
Conclusion:
Sellar/suprasellar mass without optic chiasm compression or cavernous sinus invasion. The imaging appearance and elevated prolactin are consistent with pituitary macroadenoma, containing a region of cystic degeneration.
The patient went on to have a transphenoidal resection.
MICROSCOPIC DESCRIPTION:
The sections show a moderately cellular pituitary adenoma comprising trabeculae and nests, surrounded by vascularized stroma. The tumor cells have mildly enlarged round nuclei, finely granular chromatin and moderate amounts of eosinophilic cytoplasm. There are no atypical features. No normal anterior pituitary gland tissue is present. About 50% of the tumor cells are FSH positive with moderate intensity. The Ki-67 index is about 1%. The other pituitary hormone immunostains are negative.
DIAGNOSIS:
Silent gonadotroph adenoma.