Pituitary Pathology Flashcards
Why is the posterior pituitary called the pars nervosa?
Because it originates from the nervous tissue!
The anterior pituitary has what histologic pattern? Why is this clinically helpful?
It has a honeycomb-like reticulin network that allows pathologists to distinguish it from tumors of the anterior pituitary (which will lose this structure).
The ____________ pituitary does not have as rich a network of blood vessels.
posterior (because it’s mostly axons)
Pituitary adenomas are WHO grade ____.
I (easily resectable), although they are not given this designation usually because that system is reserved for CNS tumors
Invasive macroadenomas can invade ____________.
bone
95% of pituitary adenomas are ____________.
sporadic
What is touch preparation?
If a sample of the pituitary has an adenoma, then simply touching a cytologic glass slide to it will cause shedding of cells.
Advanced pathology labs can determine which lineage of tumor the pituitary adenoma arose from by ___________.
staining for transcription factors: T-pit = corticotroph, Pit-1 = somatotroph, and SF-1 = gonadotroph
Prolactinemia can arise from three things: ________________.
pituitary tumors, dopamine antagonists, and infundibular compression (because it disrupts the tonic inhibition)
To develop true gigantism, you need to develop a pituitary adenoma before _______________.
the epiphyseal plate stops growing
Why might a prolactinoma not respond to bromocriptine or cabergoline?
If it is a mixed adenoma (with growth hormone somatotrophic cells)
Those with corticotroph adenomas might have what cell on histologic examination of their anterior pituitary?
Crooke cells –cells that change their morphology in response to high levels of cortisol
The cystic tumor that arises from the Rathke pouch is called ___________.
craniopharyngioma
Metastasis to endocrine glands is not common, but the most common cancer to do so is _____________.
breast cancer
85% of sellar masses are _______________.
pituitary adenomas