14 Nontoxic Diffuse Goiter, Nodular Thyroid Disorders, Thyroid Malignancies

Question 1

Identify the ATA risk:
Papillary thyroid cancer with no local or distant metastases

Answer 1

Low risk

Question 2

Identify the ATA risk:
Papillary thyroid cancer with all macroscopic tumor resected

Answer 2

Low risk

Question 3

Identify the ATA risk:
Papillary thyroid cancer with no tumor invasion of locoregional tissues or structures

Answer 3

Low risk

Question 4

Identify the ATA risk:
Microscopic invasion of tumor into the perithyroidal soft tissues

Answer 4

Intermediate risk

Question 5

Identify the ATA risk:
RAI-avid metastatic foci in the neck on the first posttreatment whole-body RAI scan

Answer 5

Intermediate risk

Question 6

Identify the ATA risk:
Agressive histology (e.g., tall cell, hobnail variant, columnar fell carcinoma)

Answer 6

Intermediate risk

Question 7

Enumerate three examples of aggressive histology that classifies a thyroid cancer under intermediate risk

Answer 7

Tall cell
Hobnail variant
Columnar cell

Question 8

Identify the ATA risk:
Macroscopic invasion of the tumor into the perithyroidal soft tissues (gross extrathyroidal extension)

Answer 8

High risk

Question 9

Identify the ATA risk:
Incomplete tumor resection

Answer 9

High risk

Question 10

Identify the ATA risk:
Distant metastases

Answer 10

High risk

Question 11

Identify ATA suspicion for malignancy:
Solid hypoechoic nodule with irregular margins

Answer 11

High suspicion

Question 12

FNA size cutoff:
High suspicion sonographic pattern

Answer 12

≥1 cm

Question 13

Estimated risk of malignancy:
Benign sonographic pattern

Answer 13

<1%

Question 14

Estimated risk of malignancy:
Very low suspicion sonographic pattern

Answer 14

<3%

Question 15

FNA size cutoff:
Intermediate suspicion sonographic pattern

Answer 15

≥1 cm

Question 16

Estimated risk of malignancy:
Low suspicion sonographic pattern

Answer 16

5-10%

Question 17

Estimated risk of malignancy:
Intermediate suspicion sonographic pattern

Answer 17

10-20%

Question 18

FNA size cutoff:
Low suspicion sonographic pattern

Answer 18

≥1.5 cm

Question 19

Estimated risk of malignancy:
High suspicion sonographic pattern

Answer 19

> 70-90%

Question 20

Identify ATA suspicion for malignancy:
Purely cystic nodule

Answer 20

Benign

Question 21

FNA size cutoff:
Very low suspicion sonographic pattern (2)

Answer 21

> /=2 cm
Observation without FNA is also reasonable

Question 22

FNA size cutoff:
Benign sonographic pattern

Answer 22

No biopsy

Question 23

Identify ATA suspicion for malignancy:
Partially cystic nodule without eccentric sold areas

Answer 23

Very low suspicion

Question 24

Identify ATA suspicion for malignancy:
Spongiform nodule

Answer 24

Very low suspicion

Question 25

Identify ATA suspicion for malignancy:
Partially cystic nodule with eccentric sold areas

Answer 25

Low suspicion

Question 26

Identify ATA suspicion for malignancy:
Hyperechoic solid nodule

Answer 26

Low suspicion

Question 27

Identify ATA suspicion for malignancy:
Isoechoic solid nodule

Answer 27

Low suspicion

Question 28

Identify ATA suspicion for malignancy:
Solid hypoechoic nodule with smooth margins

Answer 28

Intermediate suspicion

Question 29

ATA US features that confer high suspicion of malignancy in solid hypoechoic nodule component (5)

Answer 29

Irregular margins (infiltrative, microlobulated)
Microcalcifications
Taller than wide shape
Rim calcifications with small extrusive soft tissue component
Extrathyroidal extension

Question 30

Positive predictive value of elastography in estimating malignancy risk

Answer 30

30-40%

Question 31

Physical half life of pertechnetate

Answer 31

6 hours

Question 32

Physical half life of iodine-131

Answer 32

8.1 days

Question 33

Physical half life of iodine-123

Answer 33

0.55 day