Thyroid Nodules/Neoplasms

Question 1

Are thyroid cancers more likely in women or men?

Answer 1

Women

Question 2

Are thyroid nodules usually benign or malignant?

Answer 2

Benign (95%)

Question 3

Follicular cells

Answer 3

Line the colloid follicles
Concentrate iodine
Produce thyroid hormones

Question 4

What types of cancers come from follicular cells

Answer 4

Benign adenomas (most common)
Well-differentiated cancers (papillary and follicular)
Anaplastic thyroid cancer

Question 5

C cells

Answer 5

Also called parafollicular cells

Produce calcitonin

Question 6

What type of cancers do C cells give rise to

Answer 6

Medullary thyroid carcinoma

Younger age, high familial incidence, genetic

Question 7

Thyroid adenomas

Answer 7

Benign neoplasm derved from follicular cells
Most commonly in women over 30
Can be hyperfunctional (hot) and may/may not cause thyrotoxicosis
Can be observed and do not require further workup/treatment unless compressive or growth

Question 8

Cysts

Answer 8

15-25% of all thyroid nodules are cystic or have a cystic component
May result from intranodular ischemia that causes tissue necrosis and liquifaction
True epithelial lined cysts are rare
Do not need therapy unless compressive symptoms arise
Complete cysts are benign
Mixed lesions can harbour malignancy though

Question 9

Hyperfunctioning adenomas

Answer 9

Usually anatomically and functionally stable
Most patients do not develop thyrotoxicosis
Surgery and radioiodine therapy can be used to manage these lesions
Medical management can be used to control hyperthyroid state

Question 10

3 steps in the workup of a thyroid nodule

Answer 10

History and physical/labs
Ultrasound characterization
Fine needle aspiration characterization

Question 11

What are some concerning things on history

Answer 11

Age less than 20, or men over 40/women over 50
Males > females
Compressive or invasive symptoms
History of radiation exposure/therapy
Family history of thyroid carcinoma

Question 12

What size of a nodule do you start to worry about carcinoma?

Answer 12

2cm in diameter

Question 13

What are some concerning physical findings

Answer 13

Hard, fixed lesions
Rapid growth of mass
Pain 
Lymphadenopathy
Vocal cord paralysis
Stridor

Question 14

What would the
1. TSH
2. T4/T3
levels be in a hyperthyroid state?

Answer 14

1. Low

2. High

Question 15

TiRADs score based on findings in what 5 areas

Answer 15

Composition (solid worse than cystic)
Echogenicity (hypoechoic worse than hyper/isoechoic)
Shape (taller than wide is worse)
Margins (irregular/extensions worse than smooth)
Echogenicity (punctate foci/rim or micro calcifications)

Question 16

What is the risk of malignancy with a TiRADs score of 1 to 5?

Answer 16

1,2: <5%

3. 5%
4. 5-20%
5. > 20%

Question 17

Fine Needle Aspiration

Answer 17

Depends on skill of technician/MD
Small bore needle, local anaesthetic
Get Bethesda Characterizations (benign to malignant)

Question 18

Radioisotope imaging

Answer 18

Can be used to determine if a thyroid nodule is functioning
80-85% are cold
Hot nodules do not need a FNA!