Thyroid and Parathyroid Flashcards
Parafollicular C cells derived form………. produce……. which does what?
derived from neural crest, produce calcitonin (decr serum calcium)
T3: ____ times as active as t4, half life= _____
3 times as active; 3 days half life
PTU: prevents ______; crosses placenta -> ______; rare but dreadful _______
DIT, MIT coupling; crossess placenta -> cretinism; rare but dreadful aplastic anemia
____, ____, ___ all block peripheral conversion of T4 to T3
PTU; Propranolol, Prednisone
Wold Chaikoff effect: high __ doses do what? useful in what?
high I-doses (lugol’s, KI) inhibit TSH, useful in thyroid storm
FNA cannot distinguish malignant/benign with ____ and ____; what do you need?
follicular and Hurthle cell; need tissue
Most common thyroid cancer; what %?
Papillary throid CA (85%, P for popular)
Papillary thyroid cancer:
Spread? How do nodes predict survival?
___% of adults and ___% of children are node positive
Lymphatic spread, but nodes don’t predict survival;
20% of adults, 80% of children node positive; 80% are multicentric
psammoma bodes on path of what cancer? what does it represent?
papillary thyroid cancer, represents deposited calcium
History of exposure to _____ incr risk of papillary thyroid cancer
radiation
F:M ratio in papillary thyroid ca: ____
1/2 papillary thyroid cancer presents before age ___
3:1; age 40
MACIS criteria for thyroid carcinoma
Mets, age (M>50, F>40 is worse), completeness of resection, invasiveness and size (>1.5cm generally means total thyroidectomy needed)
Follicular thyroid CA:
___ Spread? ___% present with mets; F:M ratio ___? Present a older/younger? _____; Needle dx adequate? ___; Rx? ____
Spreads hematogenously; 60% present with mets; presents a little older (50s); also F:M 3:1; needle dx NOT adequate; generally do total thyroidectomy with ablative RI post-op
Medullary thyroid CA (MTC): 20% have ____
MEN2 (tend to be bilateral, younger, worse prognosis)
Amyloid on path of thyroid tissue….
Pathognomonic for medullary thyroid CA
____ is used as provocative test for medullary thyroid CA
gastrin (incr calcitonin)
This cancer originates from parafollicular C cells
Medullary thyroid CA
RET proto-oncogene is diagnostic for __________
medullary thyroid CA
Medullary thyroid CA Rx? what if node +?
Total thyroidectomy, neck dissection if node (+)
Which more likely cancer- cold/hot nodule?
cold, duh
1st step in work-up of thyroid nodule after H&P is ____
FNA (Every year)
When to operate on thyroids when pregnant? ____;
Use radioactive iodine?
Operate in 2nd trimester if possible; no radioactive iodine during pregnancy
Radioactive iodine only useful for __________
well-differentiated tumors (papillary and follicular)
Super laryngeal n., external branch: motor _______ injury _____ sensory _____
motor to cricothyroid muscle, injury= loss of projection, high pitch; provides sensory to supraglottis
