Pathology of the Pituitary Gland (Handorf) Flashcards
What bony landmarks surround the pituitary?
sella turcica
ant. and post. clinoid processes
Why is an MRI better for viewing the pituitary than a CT?
no bony artifact
The 50% of cells in the pituitary secrete what hormone?
GH
Cells secreting ____ have the largest secretory granule diameter.
PRL
How can you tell if you are looking at a histological image of the anterior pituitary (rather than the posterior)?
high vascularization in anterior pituitary
What are common causes of hypopituitarism?
- post-srx
- post-radiation
- cysts
- tumors
- ischemia or hemorrhage
- inflmm
- empty sella syndr
- gene deficit
Which lobe is often affected by an infarction?
anterior
What percentage of the lobe must be lost due to infarction before symptoms occur? Why?
75%; the lobe has a greater capacity than is actually needed for function
What are common causes of pituitary infarction?
DM CVA Increased intracranial pr hypoperfusion Sheehan's Pituitary apoplexy
When does Sheehan’s present?
~1 month postpartum
What inflammatory lesions may cause hypopituitarism?
- acute inflammation (sinusitis, osteomyelitis)
- granulomatous inflmm (TB, sarcoid, fungal, giant cell)
- lymphocytic (autoimmune)
What anatomic location does granulomatous inflammation favor?
base of brain (i.e. where the pituitary is located!)
What are common causes of hyperpituitarism?
- hyperplasia
- pituitary adenoma
- ectopic secretion by nonpituitary tumor
- hypothalamic disorder
What would pituitary hyperplasia look like histologically?
nodular or diffuse pattern of gland involvement, with increased cell number
Epidemiology of pituitary adenomas
30-50 y/o
What would affect how quickly a pituitary adenoma was detected?
if it is functional or nonfunctional
What is a possible serious symptom of pituitary adenomas?
with increased size, it can compress on the optic chiasm
What is the most common type of pituitary adenoma?
prolactin cell adenoma
What is notable about the frequency of GH cell adenomas?
~50% of the cells in the pituitary produce GH, but they only account for 5% of pituitary adenomas
Gross morphology of pituitary adenomas?
well circumscribed, macro or micro lesion; if large enough, may extend into suprasellar region
Histology of pituitary adenomas?
sheet-like growth pattern with relative cellular monomorphism and loss of reticular network
note: functional status cannot be predicted from routine histo appearance
How can you confirm that a tumor is a pituitary adenoma?
immunohistochemical stains
He didn’t cover a ton of slides.
Can we assume we aren’t responsible?
