Thyroid Pathology (Handorf)--non-neoplastic

Question 1

defn of gland

Answer 1

collection of cells specialized to secrete materials NOT related to their ordinary/intrinsic metabolic needs

Question 2

secrete substances that act on nearby cells

Answer 2

paracrine

Question 3

made in cell then secreted into blood where they travel to site of action

Answer 3

endocrine

Question 4

secrete substances that act on itself

Answer 4

autocrine

Question 5

pathway that thyroid gland descends during organogenesis

Answer 5

thyroglossal duct

Question 6

site or origin of thryglosal duct between the floor of bronchial arches 1 and 2

Answer 6

foramen caecum

Question 7

retrosternal thyroid

Answer 7

developing thyroid moves too far down the mediastinum during organogenesis

Question 8

Where do lingual thyroids form?

Answer 8

foramen cecum of tongue

Question 9

problems assc with lingual thyroid?

treatment of lingual thyroid?

Answer 9

difficulty swallowing and breathing (if large enough)

if you remove it, pt no loner has thyroid gland –> hypothyroid and must receive TH replacement therapy

Question 10

midline nodule vs lateral nodule around the region of the thyroid

Answer 10

midline = thryglossal duct cyst
**in kids usually

lateral = aberrant thyroid (in adults, this is metastatic follicular thyroid carcinoma)

Question 11

why does a thyroglossal duct cyst need to be removed?

Answer 11

recurrent infections!! also if big enough can obstruct the airway (and for cosmetic reasons)

Question 12

is a thyroglossal duct cyst considered an ectopic thyroid?

Answer 12

yes, but it usually is NOT hormonally active

Question 13

term for ectopic thyroid in anterior mediastinum seen with cervical goiter

Answer 13

substernal goiter

*handorf says these develop post-goiter removal/thyroid surgery when some of the thyroid is left behind –> it grows to function as thyroid that was removed?

Question 14

are substernal goiters symptomatic?

Answer 14

sometimes (trouble swallowing, breathing if be enough) hyper or hypo-thyroid

Question 15

lateral aberrant thyroid in adult is most likely…

Answer 15

metastatic follicular thyroid carcinoma

Question 16

Similar location to thyroglossal duct cyst
Often hypothyroid (absent cervical thyroid)
-may be the only thyroid tissue a person has (like lingual thyroid)

Answer 16

suprohyoid/infrahyoid thyroid

Question 17

Ectopic thyroid tissue in heart

• if this usually function?
• what part of the heart is it usually found?

Answer 17

struma cordis

functional
right ventricle

Question 18

monodermal teratoma of ovary

Answer 18

struma ovarii

Question 19

stuma ovarii are composed of mainly ____ tissue

Answer 19

thyroid

Question 20

presentation of stuma ovarii

Answer 20

woman with over thyrotoxicosis with a whole/absent thyroid (the normal thyroid goes dormant bc the ectopic one is going cray cray)

Question 21

5 pathologies causing hyperthyroidism. Which one is most common?

Answer 21

1. diffuse hyperplasia assc with Graves dz *** 85% of hyperhthyroidism
2. early stages thyroiditis
3. exogenous thyroid hormone admin
4. hyperfunctional mulinodular goiter
5. hyperfunctional thyroid adenoma

Question 22

very thin, non-pitting edema, exopthalmos

Answer 22

Graves dz

Question 23

pathogenesis of exopthalmos in graves dz

Answer 23

overstim of levator palpebrae superioris + accumulation of loose CT/GAGs behind eyes –> eyes bulge out

Question 24

pathophys of graves dz

Answer 24

Abs against TSH receptor bind to it and causes thyroid stimulation WITHOUT negative feedback
-these Abs also bind to other tissue sites and inc CT production of GAGs –> exopthalmos and non-pitting edema

Question 25

histopath buzzwords for graves dz

Answer 25

scalloped colloid and heaped up folds of papillary or hyperplastic epithelium

Question 26

6 pathologies causing hypothyroidism

Answer 26

impaired TH synthesis: iodine def or lithium
failed thyroid development (cretinism)
surgical removal or thyroid
radiation
suprathyroid lesions (aka in pit or hypothalamus)
thyroiditis

Question 27

commonest cause of hypothyroidism in N america (aka where we don’t have iodine def)

Answer 27

hashimoto thyroiditis

Question 28

etiology/pathogenesis of hashimoto thyroiditis

Answer 28

insult –> thyroid Ags recognized by T cells (+ lack of tolerance) –> activate T and B cells –>
Ab mediated damage to thyrocytes –> apoptosis
cytokines and radicals damage thyrocytes –> apoptosis
T cell cytotoxicity kill thyrocytes

=AUTOIMMUNE
(therefore Female > male)

Question 29

histo progression of hashimoto thyroiditis

Answer 29

lymphocytic infiltrate –> tissue destruction –> fibrosis

Question 30

diff between early and late hashimoto thyroidits

Answer 30

early = hyperthyroidism (inc follicles)

late = hypothyroidism (destruction and fibrosis)

Question 31

self limited, post-viral inflammatory process involving thyroid

Answer 31

subacute (granulomatous) thyroiditis

Question 32

T or F: subacute (granulomatous) thyroiditis is an autoimmune process

Answer 32

F, bc it is self-limiting

but has female predominance

Question 33

fibrosis of thyroid and other neck structures (might even have fibrosis in retroperitoneum)

Answer 33

Riedel Thyroiditis

Question 34

why is the thyroid susceptible to infection?

Answer 34

highly vascularized

Question 35

infection of thyroid + granulomas

Answer 35

milliary TB

Question 36

infection of thyroid + intralcellular inculsions

Answer 36

CMV

Question 37

mixed infalmmatory reaction with prominent multi nucleated giant cells

Answer 37

subacute (granulomatous) thyroiditis

Question 38

chronic enlargement of thyroid gland, not due to a neoplasm

Answer 38

goiter

Question 39

in what regions are goiters common

Answer 39

where glaciation has occurred (mountainous areas)

=low iodine in soil

Question 40

endemic goiters start as ______ but progress too ______

Answer 40

diffuse enlargement –> multinodular state (with episodes or regression and enlargement)

Question 41

Why do goiters get so big???

Answer 41

Hypertrophy is the compensation for the thyroid not being able to make enough T3/4, outgrows their blood supply –> necrosis and fibrosis –> grow more bc T3/4 is still low –> cycle repeats

Question 42

internal regression and cyst formation + bands of fibrosis separating these lesions

Answer 42

“colloid nodules”

-describing histopath, seen in diffuse and multinodular goiters