Pathoma: Thyroid Gland

Question 1

Thyroid development can stop at one of two places: ________________.

Answer 1

the tongue (leading to a tongue-base mass) or the neck (leading to an anterior neck mass)

Question 2

Thyroid hormone stimulates increased basal metabolic rate by _______________.

Answer 2

increasing the expression of Na/K-ATPases

Question 3

Thyroid hormone stimulates ____________ receptors.

Answer 3

beta-adrenergic

Question 4

Hyperthyroidism can cause ________-glycemia and __________-cholesterolemia.

Answer 4

hyper (because TH is a counter-regulatory hormone); hypo

Question 5

Graves’ disease results from IgG stimulation of ___________ receptors.

Answer 5

TSH

Question 6

True or false: exophthalmos and pretibial myxedema result from increased T4.

Answer 6

False! There are TSH receptors on the fibroblasts of the eye and in the shins, so IgG stimulation leads to growth of glycosaminoglycans.

Question 7

Histologically, what do thyroids with Graves disease look like?

Answer 7

The follicles will be enlarged, and there will be scalloping along the edges.

Question 8

True or false: thioamide blocks an enzyme in the cytosol of thyroid follicular cells.

Answer 8

False. Thyroid peroxidase is in the colloid.

Question 9

What are presenting signs of thyroid storm?

Answer 9

Arrhythmia, hyperthermia, hypovolemic shock, and vomiting

Question 10

Relative iodine deficiency can cause _________________.

Answer 10

multinodular goiter

Question 11

The historic term for congenital hypothyroidism is _________________.

Answer 11

cretinism (short stature, mental retardation, macroglossia, coarse facial features)

Question 12

The most common enzymatic cause of congenital hypothyroidism is _____________.

Answer 12

thyroid peroxidase

Question 13

Hypothyroidism results in _________________.

Answer 13

decreased basal metabolic rate (with weight gain despite normal intake), decreased cardiac output, and hypercholesterolemia

Question 14

What HLA is associated with Hashimoto’s?

Answer 14

HLA-DR5

Question 15

Describe the progression of Hashimoto’s.

Answer 15

Because the thyroid gets destroyed, T4 and T3 will initially be released (causing hyperthyroidism), but then the levels are exhausted and hypothyroidism ensues.

Question 16

True or false: Hashimoto’s is caused by antithyroglobulin and antimicrosomal antibodies.

Answer 16

False. While these are present in someone with Hashimoto’s, they are a result of –not a cause of –Hashimoto’s.

Question 17

A patient with Hashimoto’s presents with a greatly enlarged thyroid. What might be going on?

Answer 17

Marginal lymphoma. Hashimoto’s causes germinal centers to grow in the thyroid, which can raise risk of B-cell lymphoma.

Question 18

True or false: a young woman presents with a disorder that causes tender thyroid; she is at risk of developing to hypothyroidism.

Answer 18

False. Subacute deQuervain granulomatous thyroiditis causes a tender thyroid, but it does not lead to hypothyroidism.

Question 19

A non-tender, “hard as wood” thyroid is likely ________________.

Answer 19

Reidel fibrosing thyroiditis: a chronic inflammatory disorder that causes extensive fibrosis

Question 20

Both Reidel fibrosing thyroiditis and anaplastic carcinoma can spread to local structures. What is the best way to distinguish the two?

Answer 20

Reidel is a disease of young people (particularly women) and anaplastic carcinoma is a disease of the elderly.

Question 21

Thyroid nodules are much more likely to be _________.

Answer 21

benign

Question 22

Decreased uptake in a thyroid nodule is suggestive of ______________.

Answer 22

non-functional adenoma or carcinoma (whereas increased uptake suggests Graves)

Question 23

Follicular adenoma will present with what histologic pattern?

Answer 23

A capsule-encircled area that is more purple but still has follicles

Question 24

There are four types of thyroid carcinoma –papillary, medullary, follicular, and anaplastic. Which is the most common?

Answer 24

Papillary (80%)

Question 25

Papillary thyroid carcinoma presents with two distinct nuclear signs: ____________________.

Answer 25

Orphan Annie eyes (clearing of the nucleus) and nuclear grooves (purple lines in the nucleus)

Question 26

Histologically, how do follicular carcinoma and follicular adenoma differ?

Answer 26

Both will have a fibrous capsule, but the carcinoma will invade through the capsule while adenoma will not.

Question 27

Why can’t FNA differentiate between follicular adenoma and carcinoma?

Answer 27

Because both present with normal follicular cells in the center (where the needle will go). You need to see the borders to know which kind it is.

Question 28

Medullary carcinoma is a proliferation of ____________ cells.

Answer 28

calcitonin-secreting cells

Question 29

Medullary carcinoma presents as neoplastic cells stuck in ______________.

Answer 29

amyloid stroma (because the calcitonin can accumulate as amyloid)

Question 30

RET mutations are indicative of ________________, prophylactically.

Answer 30

thyroidectomy