Path Flashcards
2 components of pituitary gland
anterior:
- 80%
- positive and negative feedback from hypoT
- cells: acidophil, basophil, chromophobe
posterior:
- pituicytes (modified glial cells and axon terminals)
Pituitary gland:
L: superior pituitary with the stalk coming from the hypothalamus entering it. larger portion, the anterior pituitary (adenohypophysis), is toward the top.
R: inferior pituitary. posterior pituitary (neurohypophysis) is the smaller portion at the bottom.
R: adenophyphysis
L: neurohypophysis
adenohypophysis
- basophils (purple): FLAT
- gonadotropes
- corticotropes
- thyrotropes
- acidophils (pink): PiG
- mammotropes
- somatotropes
- chromophobes (clear):
- resting/degranulated chromophils
pituitary adenoma
inherited genetic defects of pituitary adenomas (4)
MEN1
CDKN1B
PRKAR1A
AIP
Abnormalities associated with aggressive behavior:
- Overexpression of CyclinD1
- TP53 mutations
- Silencing of RB
- Activating mutations of the HRAS oncogene (pituitary carcinoma)
morphology of pituitary adenomas (5)
- soft & well circumscribed
- uniforme polygonal cells
- sparse CT/reticulin
- sparse mitotic activity
- uniform cytoplams (dependent of type of hormone produced)
Prolactin can be demonstrated within the secretory granules in the cytoplasm of the cells using _____ stains
IHC
corticotroph adenomas stains:
PAH: carb in POMC
ICH: POMC, ACTH, beta-endorphin
The most common cause of Secondary Hyperthyroidism is ….
TSH secreting pituitary adenoma
primary empty sella v secondary empty sella
primary:
defect in diaphragm sella –> arachnoid mater & CSF –> herniate into sella –> expand & compress pituitary
- obese women with multiple pregnanacies
- presentation:
- visual field defects
- endocrine anomalies (hyperprolac)
secondary:
mass enlarges in sella –> sx removal/infarcton –> loss of pituitary function
what type of distribution do Craniopharyngiomas have?
•Bimodal distribution –
–Peak in childhood (5 – 15 years)
–Peak in adulthood > 65 years
dx features of craniopharyngiomas (4)
adamantinomatous type (children):
- nests/cords of stratified sq epithelium embedded in spongy reticulum
- palisading sq epithelium in periphery
- wet keratin (compact lamellar keratin)
- dystrophic calcifications
papillary type (adult):
solid sheets & papillaie lined by sq epithelium
Pregnancy-Related Thyroid Disease
↑ estrogen –> ↑ TBC
hCG (+) thyroid hormone –> downregulation of TSH in 1st trimester
- returns to normal in 2nd & 3rd trimester
