Pituitary Pathology

Question 1

Where does most pituitary pathologies occur - anterior or posterior?

Answer 1

anterior

Question 2

What is the mnemonic to help remember what hormones are secreted by the basophils of the atnerior pituitary?

Answer 2

B-FLAT

Basophils secrete FSH, LH, ACTH and TSH

Question 3

So what two hormones come from the acidophils?

Answer 3

growth hormone and prolactin

Question 4

What two hormones are released by the posterior pituitary? Where are they made though?

Answer 4

oxytocin and ADH (vasopressin)

made in the hypothalamus

Question 5

What are the things oxytocin is associated with?

Answer 5

labor
milk let-down

cuddling (after orgasm)
monogamy (in vole studies)
trust (investment experiment)

Question 6

Hyperpituitarism causes too much hormone from the ____ pituitary

Answer 6

anterior pituitary

Question 7

What are the 5 potential causes of hyperpituitarism?

Answer 7

pituitary adenoma (BY FAR the most common)

destruction of end organs (loss of negative feedback)

hypothalamic disorders (rare)

hyperplasia of atnerior lobe (rare)

carcinoma of anterior lobe (rare)

Question 8

True or false: it takes a while for symptoms to show for pituitary adenomas

Answer 8

true

Question 9

Why can pituitary adenomas cause visual deficits?

Answer 9

mass effect (especially the non-functional big ones) - bitemporal hemianopsia

can also cause increased intracranial pressure and HYPOpituitarism (if a big non-functional squishes the rest of the functional pituitary)

Question 10

How big must a pituitary adenoma become in order to be considered a macroadenoma?

Answer 10

1 cm

Question 11

True or false: pituitary adenomas are usually invasive

Answer 11

false

but some can grow aggressively fast and grow out of the sella - NOT malignant though

Question 12

What tumor syndrome can pituitary adenomas be associated with?

Answer 12

MEN 1

Question 13

What is the microscopic appearance of a pituitary adenoma?

Answer 13

1. sheets/cords
2. uniform cells of one type
3. may be pleomorphic
4. may have mitoses

Question 14

True or false: you can usually tell the hormonal type of pituitary adenoma based on microscopic appearance.

Answer 14

false

Question 15

What is the most common hormone to be produced by a pituitary adenoma?

Answer 15

prolactin

Question 16

What is the least likely hormone to be produced by a pituitary adenoma?

Answer 16

TSH

Question 17

What are the 4 general classes of genes that can be mutated in pituitary adenoma?

Answer 17

1. mutated GNAS1 gene
2. mutated MEN-1 gene
3. Mutated RAS
4. Mutated c-MYC

Question 18

What is the term for the most common type of pituitary adenoma?

Answer 18

Prolactinoma

Question 19

What are the symptoms of a prolactinoma?

Answer 19

amenorrhea

galactorrhea

Question 20

How do we treat prolactinomas?

Answer 20

dopamine receptor agonists

Question 21

What will occur in a pre-pubertal growth hormone adenoma?

Answer 21

gigantism

Question 22

What will occur in a post-pubertal growth hormone adenoma?

Answer 22

acromegaly

Question 23

What are some additional manifestations of growth hormone adenomas?

Answer 23

diabetes mellitus
hypertension
arthritis
gastrointestinal carcinoma

Question 24

What would be the laboratory findings in a GH adenoma?

Answer 24

1. increased GH (that comes in spurts)
2. increased IGF-1 (makes a better marker)
3. GH will be unresponsive to glucose (it should go up)

Question 25

What are the three diseases/syndromes that occur with an ACTH adenoma?

Answer 25

``` Cushing syndrome (high cortistol in blood) Cushing disease (from pituitary adenoma) Nelson syndrome (if you take out the adrenals by mistake, the adenoma loses the cortisol inhbition and it grows huge) ```

Question 26

What happens in a pituitary cushing syndrome?

Answer 26

the anterior pituitary makes too much ACTH, leading to too much cortisol, leading to cushings

Question 27

What happens in an adrenal cushing syndrome?

Answer 27

there's normal ACTH, but the adrenal gland either has a tumor secreting cortisol or nodular hyperplasia secreting cortisol

Question 28

Cancer of what organ will most often cause a paraneoplastic cushing syndrome?

Answer 28

lung cancer - the tumor secretes ACTH, which promotes adrenal hyperplasia and increased cortisol

Question 29

What happens to the adrenal gland when there is iatrogenic cushing syndrome from long-term steroid use?

Answer 29

adrenal atrophy

Question 30

What do FSH/LH adenomas and non-functioning adenomas have in common?

Answer 30

they can get really big because they present late without the endocrine symptoms

Question 31

What are the 5 general causes of hypopituitarism?

Answer 31

1 pituitary destruction 2. ischemic necrosis 3. empty sella syndrome 4. pituitary apoplexy 5. hypothalamic lesions

Question 32

What are two ways the pituitary can be destroyed?

Answer 32

1. by a big pituitary adenoma | 2. by surgery or radiation

Question 33

What are the two reasons that the pituitary can undergo ischemic necrosis?

Answer 33

1. For whatever reason, the pituitary gets BIG, but blood flow remains the same (USUALLY PREGNANCY) 2. Hemorrhage elseqhere causes hypotension and decrease in perfusion result: the pituitary (which is already hypoxic) becomes necrotic

Question 34

Describe what happens in empty sella syndrome.

Answer 34

you can get arachnoid or CSF herniation into the space leading to pituitary compression and what looks like an empty sella on MRI

Question 35

True or false:empty sella syndrome is usually associated with hypopituitarism.

Answer 35

false usually still have enough pituitary to make enough hormone to be asymptomatic

Question 36

What causes pituitary apoplexy?

Answer 36

sudden infarction of an adenoma remember they can bleed quite suddenly

Question 37

What type of symptoms will pituitary apoplexy present with?

Answer 37

meningeal symptoms

Question 38

True or false: the clinical onset of hypopituitarism is usually insidious and chronic.

Answer 38

true

Question 39

How many hormones are usually affected by hypopituitarism?

Answer 39

one or two panhypopituitarism is rare

Question 40

What is the order of hormones affected by hypopituitarismfrom most common (first) to least common (last)?

Answer 40

GH FSH/LH TSH ACTH

Question 41

What happens with too little GH?

Answer 41

pituitary dwarfism | muscle weakness

Question 42

What happens with too little FSH/LH?

Answer 42

loss of libido | menstrual abnormalities

Question 43

What happens with too little prolactin?

Answer 43

inability to lactate

Question 44

What happens with too little TSH?

Answer 44

hypothyroidism

Question 45

What happens with too little ACTH

Answer 45

adrenal insufficiency

Question 46

What are the two posterior pituitary syndromes?

Answer 46

1. diabetes insipidus | 2. Syndrome of Inaporporpiate ADH secretion

Question 47

What happens in diabetes insipidus?

Answer 47

decreased ADH pee dilute urine serum osmolality incresaes increase water intake

Question 48

What happens in syndrome of inappropriate ADH secretion?

Answer 48

increased ADH retain water blood becomes hypotonic decreased water intake

Question 49

What type of cancer can cause SIADH?

Answer 49

small cell lung CA with ectopic ADH production