What are the two most common types of pituitary adenoma?
Prolactinoma (30%) - acidophil
Null-cell/non-secreting (25%) - mass effect/hypofx
Can be GH or ACTH
What are micro characteristics of pituitary adenomas?
One cell type
Reticulin meshwork/clusters gone
All cells stain with one antibody - order panel
What symptoms might this present with?
Prolactinoma - galactorhea, amenorrhea, erectile dsyfunction
Null-cell - mass effect, panhypopit, visual disturbances
Which of these is a pituitary adenoma?
Left - all one cell type, loss of reticulin meshwork
Where are Rathke Cleft Cysts located and what symptoms might it produce?
Sella or suprasellar location
Asymptomatic, or stalk effect
What is this and is it malignant?
Rathke Cleft Cyst
No, its a remenant of rathke's pouch during development
Who gets craniopharyngiomas, how does it present, and is it malignant?
Children and adults - bimodal peak
Hemianopsia (commonly suprasellar), Hypopituitarism, Stalk Effect
No - benign
What is the difference between adamantinomatous and papillary type craniopharyngiomas?
Adamantinomatous: Dark brown fluid filled cysts, basally palisading squamous epithelium, abundant keratin, local invasion w/ chronic inflammatory
Papillary type: Papillary architecture, no keratin formation
What is this?
Adamantinomatous Type Craniopharyngioma
Which pharyngeal pouches does the parathyroid develop from?
3rd: Inferior and thymus
What cells is the parathyroid composed of?
Chief cells (PTH) and oxyphil cells
Large amount of intervening stromal fat (30-70%)
In this normal parathyroid, which cells secrete PTH?
Chief cells on the left
What are the 3 main causes of primary parathyroid hyperfunction?
- Parathyroid Hyperplasia | 10-15%
- Parathyroid Adenoma | 75-80%
- Parathyroid Carcinoma | <5%
What are the primary causes of parathyroid hypofunction?
- Congenital - DiGeorge (22q11)
What is this and what causes it? What else might you see in this disease?
Osteitis fibrosa cystica - High PTH (Adenoma, hyperplasia)
Thinned cortex, fibrosis of marrow with hemorrhange and cyst formation.
What characterizes this tumor and what causes it?
Brown tumor: OC, reactive giant cells, hemorrhage
How do you distinguish parathyroid adenoma from parathyroid hyperplasia?
Adenomas are larger (.5-5g)
Decrease in stromal fat
May show a rim of normal parathyroid
What is this?
What are characteristics of parathyroid hyperplasia?
All 4 glands involved
No rim of normal
How is parathyroid carcinoma diagnosed?
When they become clearly invasive or malignant
Cellular atypia is not a reliable feature of malignancy!
Difficult to remove due to thick fibrous bands
What are characteristics of adrenocortical hyperplasia?
Bilateral thickening of cortex - diffuse or nodular
Predominantly fasciculata cells - clear cells
What is this? What other characteristics is it likely to have?
Non-functional (majority, clinical)
Predominantly zona fasciculata cells - clear, lots of cytoplasm, round eccentric nuclei
These are to samples from different adrenal gland masses. If the mass is >5cm and is invading through the capsule and into the adrenal vein what is it and what other characteristics does it have?
>5cm, capsular invasion, necrosis, hemorrhage, well-poorly differentiated, invades adrenal vein and vena cava, LN mets, pleomorphism
Can't differentiate from adenoma - invasion
What are the main causes of ACTH independent hypercortisol?
Adrenocortical adenoma or carcinoma
What is the main cause of bilateral adrenal hyperplasia in the setting of hypercortisol?
Pituitary Adenoma - Inc. ACTH
A patient presents with headaches, palpitations, and diaphoresis. What does he likely have and what is cell origin, and what is the microscopic appearance? Is it malignant?
Pheochromocytoma - chromaffin cells
Zellballen - nests of cells, very vascular, abundant granular basophilic cytoplasm, variable
Stain with chromogranin and synaptophysin
Stain for synaptophysin and chromogranin
Only if it presents with mets!
10% of pheos are extra-adrenal, what are the most common sites are these funcitonal?
Paragangliomas most commonly occur on the sympathetic chain (jugulotympanic, carotid body, vagal, and aorticopulmonary)
No, they look similar to pheos i.e. Zellballen
What is the rule of 10 for pheochromocytomas?
10% extra-adrenal (Paraganglioma, non-functional)