ATA 2014 Flashcards
How long should a patient with Grave’s disease be treated with methimazole?
12 - 24 months.
Stop if TSH is normal at that time.
Which is bigger: TR alpha or TR beta?
TR beta
What percentage of people are ‘cured’ of hyperthyroidism with radioactive iodine therapy?
80%
Pre-operative potassium iodide should be given to Grave’s disease patients
True or false?
True
Does maternal TSH cross the placenta?
No
Does maternal T4 cross the placenta?
Yes - in low amounts.
Gestational thyrotoxicosis is secondary to elevation of which hormone?
Beta hcg.
How much PTU is 10 mg of methimazole equivalent to?
100 - 150 mg
Which crosses the placenta more: T3 or T4?
T4
Is levothyroxine alone or combination thyroid hormone therapy preferable in pregnancy?
Levothyroxine alone.
Approximately how much maternal T4 crosses the placenta?
About one third of T4.
What’s the starting dose of levothyroxine in infants?
10 - 15 mcg/kg/day
What percentage of the world birth population undergo newborn hypothyroidism screening?
30%
Should you biopsy a thyroid nodule that is less than 1 cm?
No.
Not even if looks suspicious
Should you do a lateral neck dissection without doing a biopsy of the lymph nodes?
No.
If you can’t - then at least do a neck ultrasound to look at the lymph nodes.
If you see suspicious lymph nodes which imaging studies should you do?
Neck ultrasound for surgical planning.
Lymph node survey
If a differentiated thyroid cancer / highly suspicious nodule is less than 1 cm in an old patient - can it be followed?
Yes - in selective cases.
If a thyroid mass (biopsy proven cancer) is fixed to structures in the neck should the vocal cords be looked at prior to surgery?
Yes
Patients with differentiated thyroid cancer > 1 cm and < 4 cm with no extra thyroidal extension and no lymph nodes - which surgery would to do?
Lobectomy/hemithyroidectomy
Near-total/total thyroidectomy
What are the approximate doses of radioactive iodine for:
- Remnant ablation
- Adjuvant treatment
- Treatment of distant metastasis
- Remnant ablation (30 mCi)
- Adjuvant therapy (30 - 100 mCi depending on risk)
- Treatment of distant metastasis (100 mCi or more)
Generally do surgeons use pharmacological DVT prophylaxis perioperatively for thyroidectomies?
No - bleeding risk (life threatening neck hematoma) too great.
Which germline mutation is associated with medullary thyroid cancer?
RET mutation.
Once you have reached 600 mCi of radioactive iodine what’s the likelihood that you will be able to cure the patient with radioactive iodine?
Very low likelihood.
What’s one the most commonly reported mutations reported in differentiated thyroid cancer?
BRAF
What iodide transporter - other than pendrin - causes iodide efflux from thyroid cells?
Anoctamin 1
What gene mutation is present in medullary thyroid cancer?
RET gene mutation
75% or more of MEN 2B are typically de novo disease.
True or false.
True
What levels are followed in MEN 2 in patients with medically thyroid cancer?
Calcitonin
Calcitonin less than 30 - 60 pg/mg in children with medullary thyroid cancer suggest no lymph nodes involved.
True or false?
True
What’s better for medically thyroid cancer: ultrasound or calcitonin?
Calcitonin
What disease will you think of if you see hypertrophic ganglia (after surgery)?
MEN 2B
What should you check before taking medullary thyroid cancer patient to the OR?
Plasma metanephrines
Which is better for looking for metastasis in medullary thyroid cancer:
CT or PET?
CT
Can pheochromocytomas present as cystic masses?
Yes
What happens to the size of nerves in MEN 2B?
Enlargement.
What is the median survival in medically thyroid cancer with distant metastasis?
3 years
Is the calcitonin doubling time a good prognostic factor for medullary thyroid cancer?
Yes
What type of CT should you do in neuroendocrine tumors?
Triple phase CT
What are the three major pathways that are targets of chemotherapy in medullary thyroid cancer?
RET
RAF
VEGFR
Have any of the treatment options for metastatic medullary thyroid cancer shown a survival benefit?
No
Does Afirma have a greater positive predictive value or negative predictive value?
Negative predictive value.
Should you biopsy an FDG positive nodule found on PET scanning?
Yes
Unless it’s very small
If you have a small thyroid nodule (less than 1 cm) but an enlarged lymph node in the neck - then do you biopsy the thyroid nodule?
Yes - in addition to the lymph node.
Is an intrathyroidal parathyroid carcinoma a neural crest tumor?
Yes
Which acts on the cardiac myocyte:
T3 or T4?
T3
What vascular pattern do parathyroid glands have on ultrasound?
Polar vascular pattern
Which BRAF mutation is most strongly (more than 80%) associated with thyroid cancer?
V600E
Is BRAF mutation a prognostic marker for mortality?
No
When should the presence or absence of BRAF mutation be a factor in selection of patients with metastatic thyroid cancer for chemotherapy?
When considering tyrosine kinase drugs that inhibit BRAF pathway.
VEGF pathway is specific for angiogenesis.
True or false?
True
Does anti-VEGFR therapy improve or worsen survival?
Either no effect or slightly worsened.
PDGFR expression promotes nodal metastasis in papillary thyroid cancer.
True or false?
True
What determines prognosis in differentiated thyroid carcinoma?
Histology
What dose of radioactive iodine for remnant ablation in differentiated thyroid cancer?
30 mCi.
What does pregnancy do to antibody levels?
Typically it decreases them.
What happens to the creatinine in hyperthyroidism?
It is falsely lowered.
Should you give diuretics to patients with very uncontrolled hyperthyroidism?
Not usually - may cause blood pressure to drop.
What is the daily requirement for iodine intake?
150 mcg/day
How long should you wait before doing a repeat biopsy if indicated non-urgently?
6 months
What three structures are removed in a radical neck dissection?
- Sternocleidomastoid
- Accessory nerve
- Jugular vein
In diffuse uptake of radioactive iodine in an uptake scan done for thyroid cancer should you give higher dose or lower dose of radioactive iodine for treatment?
Lower
What do the following findings on thyroid ultrasound indicate:
- Vascularity (increased or decreased)
- Halo (presence or absence)
They don’t indicate whether a nodule is benign or malignant anymore.
How long does calcitonin take to fall to very low levels after surgery for medullary thyroid cancer?
About 6 weeks.
How long does it take for CEA to fall to very low levels in medullary thyroid carcinoma after surgical resection?
2 - 3 months.