Thyroid Neoplasia + Diseases of Parathyroids (Handorf)

Question 1

Thyroid nodules are more likely to be neoplastic when they are:

Answer 1

solitary, in younger patients, in male patients, and in patients with a hx of radiation to head/neck

Question 2

(Hot/cold) nodules are almost always benign, while (hot/cold) are malignant 10% of the time.

Answer 2

hold

cold

Question 3

Benign thyroid nodules:

Answer 3

“Colloid” nodules
Follicular adenomas
Cysts

Question 4

Malignant thyroid nodules:

Answer 4

Papillary carcinoma (75-85%)	
Follicular carcinoma (10-20%)
Medullary carcinoma (5%)
Anaplastic carcinoma (<5%)

Question 5

Rapid and cost effective diagnostic technique for thyroid nodules.

Answer 5

Needle aspiration + cytologic evaluation of aspirated material

Question 6

How do you distinguish between benign and malignant follicular lesions?

Answer 6

Examine surgically excised tissue for capsular +/- vascular invasion

*cannot distinguish by FNA; cytologic characteristics (nuclear features, mitotic figures, etc) are the same for both benign and malignant follicular lesions

Question 7

Describe histological characteristics of follicular adenomas.

Answer 7

Solid, trabecular, or follicular pattern with NO microscopic capsular invasion; produces colloid to some extent

Question 8

What type of thyroid malignancy occurs before 40 y/o? After 40 y/o?

Answer 8

before = papillary and follicular carcinomas

after = medullary and anaplastic tumors

Question 9

Key factors in the prognosis of thyroid carcinomas?

Answer 9

age and spread beyond capsule at diagnosis

Question 10

What is the prognosis of medullary carcinoma relative to that of papillary carcinoma?

Answer 10

they are similar

Question 11

What is the prognosis of follicular carcinoma relative to that of papillary carcinoma?

Answer 11

papillary has a higher 5 and 10 year survival

p = 92% and 87%, compared to f= 74% and 66%

Question 12

All papillary thyroid lesions are classified as

Answer 12

carcinomas

Question 13

Describe gross appearance of papillary carcinomas

Answer 13

less circumscribed than benign lesions

Question 14

Papillary carcinoma in thyroid tends to produce:

Answer 14

lamellar calcified structures known as “psammoma” bodies.

Question 15

Describe gross appearance of follicular carcinomas

Answer 15

less circumscribed than benign lesions

Question 16

Histologically, what distinguishes follicular adenoma from follicular carcinoma?

Answer 16

presence of capsular and vascular invasion in carcinoma

Question 17

What are medullary carcinomas? What is a characteristic symptom?

Answer 17

Tumor of the parafollicular cells (“C cells”)

**these cells are responsible for producing calcitonin, so patients present with hypocalcemia

Question 18

Describe gross/histological characteristics of medullary carcinomas

Answer 18

solitary or multiple/bilateral

typically produce amyloid

Question 19

80% of medullary carcinomas are ______; the rest are associated with:

Answer 19

sporadic

MEN II or non-MEN familial

Question 20

What is the prognosis of Anaplastic Carcinoma?

Answer 20

“terrible”–typically invade locally and metastasize widely

Question 21

Mean age of Anaplastic Carcinoma?

Answer 21

65

Question 22

What are common disorders associated with anaplastic carcinoma?

Answer 22

• -history of thyroid disease (goiter or differentiated carcinoma)
• -20-30% have concurrent differentiated carcinoma (often papillary)

Question 23

Theorized that anaplastic carcinoma develops in the context of:

Answer 23

other tumors with loss of p53 tumor suppressor gene

Question 24

What type of lymphomas are most commonly malignant thyroid tumors?

Answer 24

B-cell lineage

Question 25

What are symptoms of thyroid lymphomas?

Answer 25

1. rapidly enlarging goiter

2. disease limited to thyroid (~50% of patients)

Question 26

Known risk factors of thyroid lymphomas?

Answer 26

Pre-existing chronic autoimmune (Hashimoto’s) thyroiditis

Question 27

What are common characteristics of small cell carcinoma of the thyroid?

Answer 27

• -highly malignant

- -usually metastatic at time of initial diagnosis

Question 28

What types of thyroid carcinoma may develop in struma ovarii?

Answer 28

1. follicular carcinoma
2. papillary carcinoma
3. very poorly differentiated and difficult to classify

Question 29

What was responsible for thyroid malignancies in Chernobyl?

Answer 29

radioactive materials, most notably I-131 (half-life of 8 days), Cs-134 (half-life of 2 years), and Cs-137 (half-life of 30 years)

Question 30

The 2 inferior parathyroids develop from:

Answer 30

third branchial pouch (also gives rise to thymus)

Question 31

The 2 superior parathyroids develop from:

Answer 31

fourth branchial pouch

Question 32

Normally, the four parathyroids are located:

Answer 32

posterior to the thyroid at the upper and lower poles

Question 33

Most common disorder of parathyroid

Answer 33

Parathyroid adenoma

Question 34

How does parathyroid adenoma affect the parathyroid?

Answer 34

• -gland increases in size

- -PTH produced in excess with resultant hypercalcemia

Question 35

How are parathyroid adenomas found?

Answer 35

routine blood tests have elevated blood calcium and PTH levels

Question 36

Clinical triad of parathyroid adenomas

Answer 36

“Moans, bones, and stones”

1. depression (+ muscle weakness)
2. bone density diminished
3. kidney stones

Question 37

Pathologically, parathyroid adenomas are distinguished by:

Answer 37

1. larger than normal

2. lacking in usual complement of fat seen in normal parathyroids

Question 38

Parathyroid hyperplasia is defined as:

Answer 38

absolute increase in the mass of the parenchymal cells of the parathyroid gland, usually involving all of the glands

Question 39

Majority of cases of parathyroid hyperplasia are secondary to:

Answer 39

hyperplasia of chief cells

Question 40

What are presenting symptoms of parathyroid hyperplasia?

Answer 40

increase in serum calcium (due to increased PTH production)

Question 41

If all or most of the parathyroid glands are enlarged, a diagnosis of ______ is likely.

Answer 41

hyperplasia

Question 42

If only one parathyroid gland is enlarged, a diagnosis of _____ is favored.

Answer 42

adenoma