15. 7 Thyroid Neoplasia

Question 1

In general, thyroid cancer presents as

Answer 1

a distinct solitary nodule

Question 2

is a thyroid nodule more likely to be benign or malignant?

Answer 2

benign

Question 3

Increased radioactive iodine (123) uptake (‘hot’ nodule) is seen in

Answer 3

Graves or nodular goiter

Question 4

Decreased radioactive iodine (123) uptake (‘cold’ nodule) is seen in

Answer 4

adenoma and carcinoma (often warrants biopsy)

Question 5

how do you biopsy a thyroid nodule?

Answer 5

fine needle aspiration

Question 6

benign proliferation of follicles surrounded by a fibrous capsule; usually nonfunctional, but may secrete thyroid hormone

Answer 6

Follicular adenoma

Question 7

Most common type of thyroid cancer

Answer 7

papillary carcinoma

Question 8

major risk factor for thyroid papillary carcinoma

Answer 8

exposure to ionizing radiation

Question 9

Histology of thyroid papillary carcinoma

Answer 9

PSAMMOMA BODIES & ORPHAN ANNIE EYES
comprised of papillae lined by cells with clear, “Orphan Annie eye” nuclei and nuclear grooves; papillae are often associated with psammomma bodies

Question 10

prognosis of thyroid papillary carcinoma

Answer 10

excellent (10 year survival > 95% even though it often spreads to cervical lymph nodes)

Question 11

to which lymph nodes does papillary thyroid carcinoma usually spread?

Answer 11

cervical

Question 12

Malignant proliferation of follicles surrounded by a fibrous capsule with invasion through the capsule; the ENTIRE capsule must be examined microscopically to diagnose

Answer 12

Follicular carcinoma

Question 13

Can diagnosis of thyroid follicular carcinoma be made with FNA?

Answer 13

NO! FNA only examines cells and not the capsule.

Question 14

How does thyroid follicular carcinoma metastasize?

Answer 14

Hematogenously

Question 15

Malignant proliferation of parafollicular C cells

Answer 15

medullary carcinoma

Question 16

What are c cells?

Answer 16

neuroendocrine cells that secrete calcitonin

Question 17

What does calcitonin do?

Answer 17

lowers serum calcium by increasing renal calcium excretion but is inactive at normal physiologic levels

Question 18

high levels of calcitonin produced by medullary carcinoma may cause

Answer 18

hypocalcemia

Question 19

calcitonin often deposits within thyroid medullary carcinoma tumor as

Answer 19

amyloid

Question 20

thyroid medullary carcinoma on biopsy

Answer 20

sheets of malignant cells in an amyloid stroma

Question 21

familial cases of thyroid medullary carcinoma as often due to

Answer 21

MEN2a and MEN2b

Question 22

MEN2a and MEN2B are associated with mutations in the

Answer 22

RET oncogene

Question 23

Detection of the RET mutation warrants

Answer 23

prophylactic thyroidectomy

Question 24

undifferentiated malignant tumor of the thyroid usually seen in the elderly that often invades local structures, leading to dysphagia or respiratory compromise

Answer 24

anaplastic carcinoma

Question 25

prognosis of anaplastic carcinoma?

Answer 25

poor