endocrine Flashcards
what is the embryological origin of the thyroid?
originates from the foramen cecum
when the descending tract doesnt close you can get thyroglossal duct cyst/mass
how can you assess the thyroid on physical exam
have them swallow (it should move) and stick out their tongue (it should also move)
how do you assess thyroid with imaging
U/S
if a person has a thyroid module and that is his only functioning thyroid tissue on U/S, do you still consider resection?
yes
what is the operation to remove the thyroid
sistrunk operation with removal of center of the hyoid
what % of the population has a palpable thyroid nodule
5-8% of women
1-2% men
increases with age
how do you assess thyroid nodule risk (for malignancy) via history
age (rates of cancer similar between ages but have better prognosis when younger)
sex
family history
growth symptoms of mass (rapidly growing masses are cancer until proven otherwise)
how do you assess thyroid nodule risk (for malignancy) via physical exam
- complete physical
- mass that grows fast is likely cancer but if it grows fast and is painful then resolves somewhat…unlikely to be cancer
- characterize the mass–> does it move when swallowing?
- lymphadenopathy
- voice
what is the best test for thyroid nodule risk assessment?
FNA
how do you assess thyroid nodule risk (for malignancy) via FNA
well differentiated thyroid cancer is based on age (staging differs on whether you are under or over 45)
dont investigate nodules that are less than 1 cm unless there is extension or associated LAD
atypia in a sample will likely be removed
what is the bethesda classification for thyroid cancer FNA?
- non diagnostic
- benign
- follicular lesion of unknown significance
- follicular neoplasm
- suspicious for malignancy
- malignant
what characteristics of a single thyroid nodule would suggest thyroid cancer
single nodule
calcifications
hypoechoic
taller than wide
heterogenous
hypervascular
take these ones out
indications for surgery for a multinodular goiter
- suspicion of malignancy/inability to rule out malignancy
- compressive symptoms (SOB, dysphagia, etc)
- hyperthyroidism
- cosmesis
- retrosternal goiters (hard to follow clinically and investigate, also hard to biopsy and it can only grow backwards into vital structures)
how does hyperthyroidism usually present
multinodular goiter, graves, solitary nodule
treatment for hyperthyroidism
anti thyroid medications
radioactive iodine
surgical management (not easy surgery)
what are the types of thyroid cancer
(most to least common)
- papillary
- follicular–> you need to see vascular or capsular invasion, which you can’t see on FNA, in order to determine if malignant or not–> usually do partial lobectomy to check
- medullary
- anaplastic (high mortality)
- lymphoma
- metastatic (often from breast)
risk factors for thyroid cancer
- previous radiotherapy/radiation exposure
2. family history
treatment of thyroid cancer
even for low risk thyroid malignancy you resect–> make sure to take out enough because there may be vascular and capsular invasion
(going back in a second time has high risk of hemorrhage)
lobectomy is thus primary treatment
what are the risks associated with thyroid surgery
-
damage to the recurrent laryngeal nerve
- -> also a non recurrent right laryngeal nerve goes straight across and can be easily injured - parathyroid risks–> hypercalcemia etc
- hemorrhage
what is the cause of primary hyperparathyroidism 85% of the time
adenoma of the parathyroid gland
what is the embryological origin of the 4 glands of the parathyroid
lower glands come from the branchial pouch and ascend from the thymus (can approach from the neck)
upper glands are posterior to the thyroid and come from the 4th pouch–> tend to be behind the place of the recurrent laryngeal nerve as opposed to the lower glands
how does a parathyroid nodule present
hypercalcemia
how do you assess the parathyroid gland
labs
imaging
physical exam
what are the characteristics of hypercalcemia you might expect to see in a patient with parathyroid nodule
moans bones psychic overtimes kidney stones fatigue
boney pain, abdo pain, depression, anxiety, anorexia, constipation, irritability, worsening or new depression, fractures, osteopenia or osteoporosis, polyuria, polydipsia, nocturia, pancreatitis