Endocrine Flashcards
Thyroid nodule: key history points
Radiation exposure
Breast Cancer
Hodgkins
Endocrine ROS
hot/cold intolerance
stones/bones/groans/moans
voice changes.When to perform thyroid scan?
Only after clearly documented mass and TSH axis dysfunction.
What are screening labs for MEN?
calcitonin
serum calcium and phosphate
urine calcium
urine metanephrines
Who to test for RET oncolgene?
All first degree relatives of known MENII
Ay new diagnosis of MTC
When d you order thyroglobulin levels?
After diagnosis of a well differentiated thyroid cancer, but prior to surgery.
What is only sub-type of thyroid cancer that gets a subtotal thyroidcectomy?
Papillary thyroid cancer
What is the operation for Medullary thyroid cancer?
What is the most likely additional procedure needed with MTC?
Medullary cancer is treated with total thyroidectomy, central node dissection and modified radical neck on the side of the primary mass
Need to screen for parathyroid hyperplasia with MENII before the OR as you may need to do a four gland exploration as well.
What is palliative “bail-out” for anaplastic thyroid cancer?
Debulk for symtoms where safe.
Divide the isthmus to prevent encirclement
tracheostomy
What is differential and labs for hyperthyroid patient?
Graves (Nontender, exophthalmos)
Thyroiditis
chech TSH T2, T4 antithyroid antibodies
Urgent indications for operating on hyperthyroid patient?
children
pregnant patient
non-suppressible nodule
Preop medications for thyroid storm?
- PTU - stop one week before the OR
- switch to lugol iodine solution for one week prior to the OR.
- Metoprolol for tachycardia
Definition of secondary hyperparathyroidism?
four-gland hyperplasia seen in the setting of renal failure in which there is excessive urinary losses of calcium
Work up of primary hyper PTH?
rule out bone disease from cancer.
direct assay of PTH and check it against the serum calcium on the normogram.
Check urinary calcium to rule out familial hypocalciuric hypercalcemia.
Cl/phosphate ratio > 33 consistent with hyper PTH.
In borderline cases for surgery, get bone films to check for evidence of early osteopenia or bone cyst formation.
What are criteria for intraoperative PTH after removal of gland?
If abnormal gland is removed, serum PTH should drop 50% or more from preoperative baseline within 10 minutes.
Other locations to look for PTH gland besides regular anatomy?
Look in upper mediastinum, tracheoesophageal groove, carotid sheath, thymus, etc
What do you do if you cannot find a parathyroid and have already explored extraanatomic sites?
hemi-thyroidectomy on side that is missing a gland.
What do you do after performing a hemithyroidectomy for a missing para and labs are still abnormal?
Sestamibi scan
Workup and indications for insulinoma?
Fasting insulin/glucose ratio > 0.3 is diagnostic.
- Get CT scan and explore if no stage IV disease.
Operation for pancreatic insulinoma?
Need to have ability to rapidly check insulin intraop
Intraop ultrasound
Can enucleate benign insulinomas.
Workup and indications for gastrinoma?
Baseline serum gastrin level >500 pg
paradoxic increase to 4-5X with secretin
ratio of basal acid output to maximal stimulated output that is >0.6.
Get CT scan and explore if no Stage IV disease.
Posible techniques to localize gastrinoma?
“gastrinoma triangle”
ultrasound
palpation
transilumination
What operation to do if you cannot find the gastrinoma?
Do a vagotomy to reduce ulcer risk.
repeat CT scan in 6-12 months
Laboratory diagnosis of aldosteronoma (Conn syndrome)
hypokalemia with
Aldosterone:renin ratio >30
Work up after diagnosing Conn Syndrome?
If you can medically control with captopril/sprinolactome, may do so,
Can localize with CT scan, selective venous sampling or NP-59 scan.
Workup for hypercortisolism?
Get basal cortisol levels, serum and 24-hour urine, to confirm hypercortisolism. Next determine ACTH – if decreased, autonomous production by adrenal adenoma; if it is increased, need dexamethasone suppression test – Cushing’s disease will suppress, ectopic sites will not.
What is medical treatment for bilateral adrenal hyperplasia?
mitotane
Pheo workup?
First obtain urinary measurements of VMA and metanephrine. Get calcium and calcitonin levels if family history suggestive of MEN IIA. If urinary values suggest pheo, get CT scan of abdomen and pelvis. MRI being used increasingly as study of first choice. I-131 MIBG may be helpful in delineating extra-abdominal sites of disease
Pheo preop?
Prep patient with two week of alpha blockade and aggressive fluid resuscitation. If tachycardia results, treat with beta-blocker.
How do you manage BP intraoperatively for a pheo?
Be prepared for wide swings in blood pressure – have nitroprusside, NeoSynephrine and phentolamine readily available,
Adrenal Incidentaloma?
get urinary catecholamines, cortisol and 17 ketosteroids, and serum electrolytes, to rule out function of the mass.
Still remove if suspicious or >5cm.
What are options for pituitary ACTH secreting tumor?
transphenoidal resection
Cyber Knife radiation therapy
Mitotane
Pasireotide - somatostatin analog that decreases ACTH (FDA approved 2014)
What are indications for subtotal thyroidectomy for graves disease?
cosmesis/compression symptoms
failure of PTU in pregnancy
failure of 1-2 years of PTU
What is treatment for thyroid storm?
Supportive care (ICU), may need intubation
beta-blockers for tachycardia
PTU 250 mg q4
hydrocortisone 100mg q6
How much thyroid do you leave in a subtotal thyroidectomy?
3-5 grams
What is main ICU B-blocker gtt?
propranolol
What is the preop medication for an insulinoma?
mechanism?
diazoxide
Potassium channel blocker that prevents release of insulin
Follow-up of a pheochromocytoma?
Urinary VMA every 3 months, then yearly
Screen all family members yearly for pheo, medullary thyroid cancer, hyperparathyroidism
What is work-up for surgical hypertension?
urinary VMA (pheo)
renin/aldosterone level
R>>A - renal artery stenosis
A>>R - aldosteronoma
consider CTAKey venous anatomy for right adrenalectomy?
the adrenal vein enters posteriorly into the IVC and mobilization of the right lobe of the liver is necessary if going transabdominal
Key venous anatomy for left adrenalectomy?
the adrenal vein enters posteriorly into the IVC and mobilization of the right lobe of the liver is necessary if going transabdominal.
How can you tell bilateral adrenal hyperplasia from aldosteronoma?
Captopril test (1) Give dose of captopril and measure aldosterone level before and after, if decreases, then bilateral hyperplasia
What is operation for a parathyroid carcinoma?
Enblock resection of the glad with ipsilateral thyroid lobe and MRM on that side.
Bethesda criteria for Thyroid FNA: acellular fluid/blood
Non-diagnostic - repeat FNA
Bethesda critera: Abundant hemosiderin-laden macrophages, scant benign follicular cells, some colloid, and rare Hürthle cells consistent with hemorrhagic colloid nodule.
Benign - continue ultrasound surveillance.
Bethesda Criteria: Scattered clusters of atypical follicular cells and scant colloid
AFLUS - undetermined significance. repeat FNA
Bethesda criteria: moderate to high cellularity, scant or absent colloid, and predominantly microfollicular or trabecular configuration of follicular cells.
Suspicious for malignancy - thyroid lobectomy
Follow-up for papillary thyroid cancer?
All pts get placed on Synthroid (enough to make TSH barely measurable) Follow thyroglobulin levels (marker for recurrence) Stop thyroxin for 2 weeks six weeks post-op and do total body radioactive I131 scan to detect any residual tumor for ablation Repeat radioiodine scan q 6 months for next few years
Follow-up for Medullary Thyroid Cancer
followed by calcitonin levels and DMSA scan (nuclear medicine
