Endocrine - Online MedEd - Thyroid nodules

Question 1

Thyroid nodules - what is it the real question?

Answer 1

Is this a cancer?

Question 2

Ultimate way to determine dx…

Answer 2

FNA

Question 3

Risk factors of thyroid malignancy

Answer 3

1) Patient
2) Physical exam findings
3) US findings

Question 4

Thyroid cancer - patient risk factors

Answer 4

*Patients who have received radiation to head and neck - Hodgkin lymphoma survivors
Personal history of cancer
Family history of cancer
Hoarseness (nodule doesn’t normally invade tissue)
Age <20, >60

Question 5

Thyroid cancer - physical exam risk factors

Answer 5

Fixed, firm, hard, positive LN nearby, usually contender

Most nodules don’t hurt

Question 6

US risk factors for thyroid cancer

Answer 6

Solid 
Hypoechogenic
Size > 2cm (need biopsy)
Microcalcifications
Irregular borders

Question 7

Find a nodule.. what is the first thing?

Answer 7

Check TSH
If thyroid is hyper functioning.. risk of cancer is low! (hyperthyroidism… low TSH is low risk nodule!)
-If TSH is low and T4 high –> can do RAIU scan to make sure T4 is coming from thyroid –> if lights up –> hyperthyroid and hyper functioning! Not cancer
Now treat hyperthyroidism
-What if RAIU scan is cold? Non-functioning nodule that is at risk of cancer –> will need to do US and FNA
-What if TSH is normal or low? Don’t do RAIU, this is a high risk nodule –> Get US –> going to be based on risk and size
-US shows nodule >1cm, super high risk and need FNA
-US shows <1cm, small nodule, can watch and wait and repeat US in 6-12 months –> if growing, go to FNA. But also consider background of patient like other risk factors

Question 8

Treatment of cancer…

Answer 8

Surgery
If shows not cancer… follow US 6-12 months, if bigger, re-biopsy
Keep biopsing until you get a definitive answer

Question 9

Know the 4 cancers of thyroid

Answer 9

1) Papillary
2) Follicular
3) Medullary
4) Anaplastic

Question 10

Papillary thyroid cancer

Answer 10

Orphan Annie nuclie
85-90% most common
Surgery is treatment

Question 11

Follicular thyroid cancer

Answer 11

Looks like normal thyroid
Spreads hematogenous
If gave radioactive iodine ablation –> gets ALL of the cancer (plus thyroid)
-This is the best one to have

Question 12

Medullary thyroid cancer

Answer 12

Associated with C cells and calcitonin
Calcitonin down –> hypocalcemia
-part of MEN IIA/IIb
-associated with RET oncogene and pheochromocytoma

Question 13

Anaplastic thyroid cancer

Answer 13

Happens in elderly
Locally invasive
Rapidly fatal
Chokes out the trachea, esophagus