ENDOCRINE Flashcards
The most important prognostic factors in survival of patients with differentiated thyroid cancer are
AGE, grade, extracapsular extension, distant metastasis, and size of the tumor.
basic criterion to be low risk papillary thryoid cancer and what is treatment
Partial thyroidectomy can be performed for patients with thyroid cancer that is <45 and no extracapsular invasion. However, there is some data to support doing a total thyroidectomy in this patient population, but it is not the standard of care.
Differentiated thyroid cancers The staging is as follows:
Papillary or follicular (differentiated) thyroid cancer in patients younger than 45:
Stage I: ANY T, any N, M0
Stage II: any T, any N, POSITIVE METS!
Papillary or follicular (differentiated) thyroid cancer in patients 45 years and OLDER:
Stage I: T1, N0, M0:
The tumor is 2 cm or less across and has not grown outside the thyroid.
Stage II: T2, N0, M0::
The tumor 2-4 cm across and has not grown outside the thyroid (T2).
Stage III: One of the following applies: T3, N0, M0: T3 LARGER THAN 4 cm across or has grown slightly outside the thyroid (T3),
not spread to nearby lymph nodes (N0) or distant sites (M0).
T1 to T3, N1a, M0: The tumor is any size and may have grown slightly outside the thyroid (T1 to T3). It has spread to lymph nodes around the thyroid in the neck (N1a) but not to other lymph nodes or to distant sites (M0). Stage IVA: One of the following applies:
T4a, any N, M0: The tumor is any size and has grown beyond the thyroid gland and into nearby tissues of the neck (T4a). It might or might not have spread to nearby lymph nodes (any N). It has not spread to distant sites (M0). T1 to T3, N1b, M0: The tumor is any size and might have grown slightly outside
the thyroid gland (T1 to T3). It has spread to certain lymph nodes in the neck (cervical nodes) or to lymph nodes in the upper chest (superior mediastinal nodes) or behind the throat (retropharyngeal nodes) (N1b), but it has not spread to distant sites (M0).
Stage IVB (T4b, any N, M0): The tumor is any size and has grown either back toward the spine or into nearby large blood vessels (T4b). It might or might not have spread to nearby lymph nodes (any N), but it has not spread to distant sites (M0).
Stage IVC (any T, any N, M1): The tumor is any size and might or might not have grown outside the thyroid (any T). It might or might not have spread to nearby lymph nodes (any N). It has spread to distant sites (M1).
Answer A: This is not a recognized stage in the TNM staging system
Primary hyperaldosteronism
is also known as Conn syndrome.
The most common presentation of primary hyperaldosteronism is difficult to control hypertension.
Hypertension results from unopposed aldosterone secretion which acts on the kidneys to absorb sodium and increases intravascular volume.
HYPOK and ALKalosis from:
Sodium is for potassium and hydrogen ions in the kidney which further increases sodium retention in the setting of hyperaldosteronism at the expense of decreased potassium and hydrogen ions in the serum.
Other symptoms of hyperaldosteronism are non-specific including weakness, fatigue and headaches. The net effect is hypertension, hypokalemia and alkalosis. (Sodium is retained at the expense of potassium and hydrogen ions).
Bottom Line: Hyperaldosteronism is associated with hypertension, hypokalemia and alkalosis.
Operative treatment of acute PID
Operations are restricted! to:
life-threatening infections,
ruptured tuboovarian abscesses,
Weak easy fatigue of voice after thyroid injury
what nerve
what does it innervate
where is it - land marks
EXTERNAL branch of the superior laryngeal nerve
innervation to the CRICOTHYROID muscle, which tilts the LARYNX during speaking to affect pitch
crosses the superior thyroid vessels
more than 1 cm above the level of the superior thyroid pole
stimulate the release of gastrin
Amino acids Alkaline environment Gastric distension Calcium vagal input
official rule on intraoperative time frame of PTH levels
(3-5) minute half life of parathyroid hormone (PTH).
Within 10 minutes of gland excision, a drop of at least 50% of the highest pre-EXCISION of GLAND (CAREFUL - NOT pre skin incision) value indicates complete resection of hyperfunctioning glands (choices B and C).
Failure to drop after 10 minutes does not imply the removed gland was normal (choice A). It only confirms there is remaining hyperfunctioning tissue within the body.
Even after a successful parathyroidectomy, if there are remaining glands, the patient is still at risk of developing a recurrence of hyperparathyroidism in the future (choice D).
Bottom Line: A 50% drop in parathyroid hormone (PTH) value after gland excision, as compared to the highest value either before skin incision or just before gland excision, is needed to confirm removal of all hyperfunctioning gland.
Familial Hypercalcemic Hypocalciuria
autosomal dominant disease caused by
increased calcium resorption in the kidney due to a defective PTH receptor.
(kidney is just absorbing extra calcium)
mild hypercalcemia
normal levels of parathyroid hormone.
DO NOT TREAT WITH ANYTHING
Primary hyperparathyroidism what are the lyte findings
hypersecretion of parathyroid hormone,
which acts to
increase the serum level of calcium.
Secondary effects of this hormone are a
decrease in serum phosphate levels due to poor renal reabsorption,
elevated urinary calcium levels.
increased chloride
surgical and Adjuvant for parathyroid cancer
en bloc resection with an ipsilateral thyroidectomy.
radiation post op has been shown to decrease local recurrence.
NO role for chemotherapy for these tumors
high grade versus low grade MALToma
Low grade lymphomas can be precipitated by an H.pylori infection and can be treated with antibiotics alone, which usually include Clarithromycin and Amoxicillin. Even with surrounding nodes are seen to be positive on CT
High grade lymphomas are better treated with a combination of chemotherapy and radiation. CHOP. Radiation is also used to treat high grade lymphoma.
Surgery is rarely indicated with gastric lymphoma and is only reserved for instances of perforation or uncontrolled bleeding.
If the results from the thyroid FNA are inconclusive, then the recommendation is
either repeat the procedure
or
have close follow up within three months
The majority of nodules with indeterminant FNA samples ultimately are found to be benign.
Surgery is not indicated after one failed attempt of FNA for diagnosis
percent of renal artery stenosis required for hypertension to occur
Renovascular hypertension is most commonly due to atherosclerosis of the renal artery, where
approximately 60% of the vessel needs to be occluded before hypertension will occur
where is the mean arterial pressure sensed in what is result when there is renal artery stenosis
A decrease in the mean arterial pressure is sensed by baroreceptors in the afferent arteriole which lead to stimulation of the juxtaglomerular apparatus, and ultimately activation of the renin-angiotensin axis
The overproduction of renin leads to hypertension that is difficult to manage with medications.
Patients may benefit from percutaneous transluminal angioplasty to decrease the renal artery stenosis.
The most common malignant tumor of the parotid gland is
mucoepidermoid carcinoma,
histologically consists of epidermoid and mucous cells.
low-, intermediate-, or high-grade, directly
related to the proportion of epidermoid to mucoid cells found on histologic examination.
tx of
mucoepidermoid carcinoma
treated with total parotidectomy, radical neck dissection and postoperative radiotherapy, regardless of nodal status!
CAREFUL, this is exception - as most neck disections are triggered by nodal status!!
High-grade mucoepidermoid carcinomas are highly aggressive, with a local recurrence rate of 60%, regional metastatic rate of 50%, and distant metastatic rate of 30%. These tumors are
with a 5-year survival of 50%.
Tx of far-advanced parotid gland carcinoma
prepared for an
extended, radical parotidectomy,
which may involve resection of overlying skin, adjacent mandible and soft tissue, temporal bone, and a portion of the adjacent external ear.
With advanced presentations, the facial nerve is invariably sacrificed in these patients; free tissue transfer may be necessary for repair.
The most common malignancy of the submandibular gland
adenoid cystic carcinoma
This is also the second most common of the parotid gland
propensity for perineural invasion and spread, as well as distant metastases
Tx of adenoid cystic carcinoma
Surgical management of these tumors
The most common malignancy of the submandibular gland (and the second most common of the parotid gland)
includes radical resection,
sacrificing nerves only for direct tumor extension
and
postoperative radiation therapy.
Despite this aggressive therapy, these tumors, which follow an indolent course, develop regional and distant metastases 40% of the time over a 10- to 20-year course.
Gross and histo features of pleomorphic adenoma
The most common benign lesion of the major salivary glands
Grossly,
smooth and lobular,
well-defined capsule.
Histologically, however,
epithelial and mesenchymal components
incomplete encapsulation
with pseudopod extension beyond the apparent borders of the mass.
These features account for the high recurrence rate when tumors are removed by enucleation alone.
tx of pleomorphic adenoma
resection of the tumor
WITH a margin of normal gland surrounding it.
The intimate relationship between the parotid gland and the facial nerve necessitates facial nerve identification and dissection to ensure its preservation and complete tumor extirpation.
Warthin’s tumors characteristics and treatment
are typically BENIGN (even though 10% bilateral!!)
cystic lesions
tail of the parotid gland.
often multicentric,
approximately 10% are bilateral
Treatment
superficial parotidectomy, similar to pleomorphic adenoma.
treatment of Squamous cell cancer of the parotid lobe is
another indication for a neck dissection even with clinical neg nodes!
Percent gastrinomas malig
Although slow growing, more than 60% of gastrinomas are malignant
sporatdic vs familial gastrinoma percentages
sporadic (80% of cases)
familial or inherited (20% of cases)
Male to female gastinoma ratio
There is a male preponderance, with a male-to-female ratio of approximately 2:1
Symptoms of adrenal insufficiency
reflect glucocorticoid AND mineralocorticoid deficiencies.
fever,
nausea, vomiting,
refractory hypotension,
lethargy.
Acute adrenal insufficiency is a medical emergency and should be suspected in stressed patients with a history of either adrenal insufficiency or exogenous steroid use.
hypercalcemic crisis ssx
Muscle weakness, fatigue, coma, and hypercalcemia are seen in patients with
thyrotoxicosis crisis (thyroid storm ssx
Fever, tachycardia, irritability, vomiting, and diarrhea (and diarrhea)
Laboratory findings of adrenal insufficiency include
hyponatremia,
hyperkalemia,
azotemia,
fasting or reactive hypoglycemia.
Hypercalcemia may also be present.
best test for both acute and chronic adrenal insufficiency
The rapid ACTH stimulation
(also called the cosyntropin stim test)
Synthetic ACTH (250 !g) is administered intravenously, and plasma cortisol levels are measured 30 and 60 minutes later.
Normal peak cortisol response should exceed 20 !g/dL.
the best test to establish primary hyperaldosteronism
Demonstration of an elevated plasma aldosterone concentration in the setting of suppressed plasma renin is
Cholecystokinin stimulates
contraction of the gallbladder
and
secretion of:
bicarbonate
secretin
CCK also stims release of pancreatic enzymes!
Pancreatic Polypeptide is known to
suppress bile secretion,
gallbladder contraction,
exocrine pancreatic function.
Acetylcholine effect on gastric acid and bicarb secresion
triggers the release of gastric acid
and
bicarbonate secretions.
Somatostatin is an inhibitory peptide found both in
hypothalamus
and
pancreatic delta cells
Pheochromocytomas can be localized using
Iodine-131 methyliodobenzylguanidine (I-131 MIBG) scan.
I-131 MIBG is preferentially taken up by the adrenal medulla and chromaffin tissue.
Pheochromocytomas are localized to the site of activity.
Gastrin stimulates
gastric acid secretion
pepsinogen secretion.
It also stimulates gastric mucosal growth.
Gastrin is released from
Gastrin is released from the G cells in BOTH the
antrum
and
duodenum
(CAREFUL - even thought you wouldn’t think you would want acid secreted in your small bowel - the duodenum can handle it because it has the brunner glands
The release of gastrin is stimulated by
food components contained within a meal,
especially protein digestion products
antral distention,
gastrin- releasing peptide
vagal stim
and
adrenergic stimulation (this is why you have heartburn when you are nervous)
Prolonged hypergastrinemia from any cause leads to
mucosal hyperplasia
increase in the number of enterochromaffin-like cells
Under some circumstances, gastrin is associated with the development of gastric carcinoid tumors (but NOT MALTomas)
CARFUL - H pylori is associated with MALToma (and H pylori also is assoicated with hypergastronemia)
Anaplastic thyroid carcinomas
are one of the most aggressive malignancies, with few patients surviving 6 months beyond initial presentation. These tumors affect patients 60-70 years old. Women are more commonly affected than men, with a ratio of 3:2. Typically, patients have a long-standing neck mass that enlarges rapidly. This sudden change is often accompanied by pain, dysphonia, dysphagia and dyspnea. Often the mass is quite large and fixed to the tracheolaryngeal framework, resulting in vocal cord paralysis and tracheal compression. More than 80% have jugular lymph node involvement at the time of presentation and greater than 50% systemic metastases. Most patients die of superior vena cava syndrome, asphyxiation or exsanguination.
Answers A & B & C & D: The aggressive nature of this tumor is not characteristic of these types of thyroid carcinoma.
Bilateral adrenalectomy is the treatment of choice for
bilateral adrenal hyperplasia causing Cushing’s syndrome.
It can also be considered in cases where pituitary surgery has failed.
Choice C: Primary adrenal Cushing’s syndrome can be treated with adrenalectomy and has a 90% success rate.
Choice D: Pituitary microsurgery has a 75% success rate for cure of Cushing’s syndrome caused by pituitary adenoma in experienced hands.
Choice E: When initial surgical intervention for pituitary Cushing’s has failed, reoperation or pituitary radiation may improve remission rates.
treatment of bilateral adrenal hyperplasia with or without clinical cushings
In patients with BMAH in whom aberrant hormone receptors are not present or for which no specific pharmacological blockade is available or effective:
- We suggest bilateral adrenalectomy for severe Cushing’s syndrome with urinary free cortisol (UFC) >2 times the upper limit of normal (Grade 1B). (See ‘Surgery’ above.)
- We suggest unilateral adrenalectomy in patients with moderately increased cortisol production (less than twofold increase in UFC levels) and clinical evidence of cortisol excess (Grade 2C). (See ‘Surgery’ above.)
- In patients with subclinical BMAH and normal levels of urinary cortisol, the decision between observation and surgery should be based on clinical evidence of cortisol excess (hypertension, diabetes, osteoporosis, or neuropsychological manifestations).
SIADH should be suspected with what findings
in any patient with hyponatremia, hypoosmolality, and a urine osmolality above 100 mosmol/kg. In SIADH, the urine sodium concentration is usually above 40 meq/L, the serum potassium concentration is normal, there is no acid-base disturbance, and the serum uric acid concentration is frequently low.
ADH secretion results in a concentrated urine and therefore a reduced urine volume
In most patients with SIADH, ingestion of water does not adequately suppress ADH, and the urine remains concentrated. This leads to water retention, which increases total body water (TBW). This increase in TBW lowers the plasma sodium concentration by dilution. In addition, the increase in TBW transiently expands the extracellular fluid volume and thereby triggers increased urinary sodium excretion, which both returns the extracellular fluid volume toward normal and further lowers the plasma sodium concentration.
Conn’s syndrome
PRIMARY hyperaldosteronism,
30 to 50 years
Aldosterone up
HYPER Na
Renin down
HYPO K
HYPERtension
autonomous secretion of aldosterone
causes Hypertension which supresses renin secretion by the feedback
Due to the lack of autoregulatory inhibition by renin, aldosterone secretion causes sodium retention and potassium wasting.
hypokalemia symptoms
fatigue, muscle weakness, polydipsia, polyuria, nocturia, headaches.
Addison disease is characterized by
hypotension
decreased cortisol
decreased aldosterone levels.
hyponatremia and hyperkalemia - OPOSITE of Conns
medullary carcinoma cell origin and embryo
The ventral portion of the 4th pharyngeal pouch develops into the ultimobranchial bodies early in the development of the thyroid gland.
These structures contain neural crest cells
fuse with the thyroid and lead to the formation of the parafollicular cells.
Calcitonin is the product of these “C cells”.
Medullary thyroid carcinoma is a neuroendocrine neoplasm derived from the parafollicular cells and calcitonin, therefore, can be used as a surveillance marker for recurrence following resection.
he most useful and widely used biochemical test for diagnosing carcinoid tumors in the symptomatic patient
24-hour urine 5-HIAA measurement with a sensitivity and specificity of 73 and 100%,
5-HIAA is excreted in the urine after serotonin metabolism and is measured more reliably than serotonin levels, which can vary between persons.
Platelet serotonin levels may be more sensitive than urine or blood tests but is not readily available at many institutions.
Somatostatin receptor scintigraphy scan - when is it used
considered after the diagnosis of carcinoid has been confirmed
to identify occult metastasis in patients being considered for curative resection
and
to determine if the patient is likely to respond to octreotide.
After undergoing a total thyroidectomy, patients should receive
radioactive iodine treatment to ablate the remnant thyroid bed to decrease the likelihood of recurrent disease.
Radioablation also allows the physician to subsequently follow thyroglobulin levels as a marker for thyroid cancer activity.
Patients who do not undergo radioablative therapy carry a two-fold increased mortality rate at 10 years compared with patients who receive radioablation.
what is surv to assess for recurrence follicular thyroid cancer
Following thyroglobulin levels is used postoperatively to assess for recurrence, NOT repeat ultrasounds.
asymptomatic multinodular goiter managment
has the possibility to progress to a toxic multinodular goiter if it becomes autonomously functioning, therefore treatment is warranted.
The first step is to confirm the nodules are not malignant - FNA
iodine supplements (WATCH OUT possibility of precipitating thyrotoxicosis)
Up to 80% of patients with iodine deficiency goiter will see a decrease in the size of the goiter with levothyroxine treatment
If the nodules continue to increase in size, or are too numerous to adequately sample by fine needle aspiration (FNA), a thyroidectomy may be indicated
Radioactive iodine treatment (RAI) treatment is used to treat Graves’ Disease
Congenital adrenal hyperplasia can be diagnosed by checking levels of what; and what are presentation and lab findings
INCREASED 17-OH progesterone
due to lack of an enzyme that is involved in the production of cortisol.
increased levels of 17-OH progesterone causes:
decreased cortisol levels
salt wasting which can elicit
hypotension.
Bottom Line: The most common form of CAH is 21-hydroxylase deficiency which causes salt wasting.
Calcitonin is released from
parafollicular cells of the THYROID (these are associated with medullary thyroid)
oppose PTH
stimulated by high levels of calcium
inhibits osteoclastic activity
A secondary action of calcitonin is increased phosphorus excretion in the kidney
High levels of calcitonin can be seen in medullary thyroid cancer
The cervical esophagus derives its blood supply from the
inferior thyroid artery
The inferior thyroid artery is a branch of the
thyrocervical trunk which is a branch of the subclavian artery.
What test is used to determine whether Cushing’s syndrome associated with elevated ACTH levels are caused by a pituitary adenoma or an ectopic source of ACTH production.
A high dose dexamethasone suppression test
The test is performed by administering 2 mg of dexamethasone every 6 hours for 48 hours. An elevated cortisol level after this study is diagnostic of an ectopic source of ACTH production. If there is a pituitary adenoma, the cortisol level should be suppressed after dexamethasone administration.
The first step in determining the diagnosis of primary hyperaldosteronism is
calculating the ratio of plasma aldosterone to plasma renin activity
cutoff value of 30 will provide a sensitivity of approximately 90%.
An absolute aldosterone concentration of 15 mg/dL will increase the specificity of screening and should be measured.
A 24 hour urine aldosterone level is measured after salt loading with either iv saline over 6 hours or oral salt loading over a 3 day period.
A positive test will demonstrate higher than normal levels of aldosterone in the urine.
The preferred initial test for localization is a thin cut (3 mm) CT scan
Adrenal vein sampling only if can not find adrenal adenoma if CT scan
This test in not necessary in patients younger than 40 years old with symptoms of hyperaldosteronism when a solitary adrenal mass greater than 1 cm is found on CT and a normal contralateral gland is seen.
When these conditions are met, surgical intervention is recommended without further studies.
Adrenal vein sampling is performed by measuring the aldosterone and cortisol levels in the peripheral circulation as well as the left and right adrenal veins. A ratio of aldosterone to cortisol fourfold higher on one side compared
Cushing syndrome present with
weight gain, muscle weakness, bone pain, and high blood pressure.
Functional adenocarcinoma present with
rapidly progressive Cushing syndrome
or
mixed presentations with signs of both Cushing syndrome and virilization.
Women with postnatal congenital adrenal hyperplasia due to 21 hydroxlase enzyme deficiency typically present with
virilization and hirsutism,
polycystic ovaries,
and
irregular menses.
AND have features of hypocortisolism and hypoaldosteronism.
Patients with hyperaldosteronism typically present with
hypokalemia, muscle weakness, and hypertension.
According to the TNM staging system of adrenocortical carcinoma what is T2
tumor size is > 5 cm
ANd if no fat invasion (T3), lymph nodes involvement, or distant metastasis = stage 2 for T2
adrenocortical carcinoma Stage I
Stage I is T1N0M0.
According to the TNM staging T1 is a tumor less than 5 cm with no invasion.
adrenocortical carcinoma Stage III
either T1-2, N1, M0
or
T3N0M0.
T3 is a tumor with inavsion to the fat.
This patient has neither lymph nodes involvement nor periadrenal fat invasion.
adrenocortical carcinoma Stage IV
Stage IV is either any T, any N, M1
or
T3- 4N1M0.
T4 is a tumor with organ invasion
indications for total thyroidectomy besides cancer
Grave’s disease and severe ophthalmopathy
Severe thyrotoxicosis, resistant to medical management
Multinodular goiter
treatment of Lymphoma of the thyroid
chemo and possible also xrt
Somatostatin is released from
D cells located in the antrum
stimulation for Somatostatin releas
response to an acidic environment
actions of Somatostatin
inhibition of gastrin
inhibition bicarbonate secretion
These actions are generated by paracrine effects on parietal and G cells
GIST location with best prognosis
primary gastric gastrointestinal stromal tumors (GIST) seeming to fare better than those of small bowel or rectal origin.
The most common locations for GIST
stomach (60% to 70%),
small bowel (20% to 25%),
colorectum (5%)
esophagus (5%).
Biopsy of GIST
NO Percutaneous core or intraoperative biopsy of a suspected GIST that is localized and presumed to be resectable
-tumors tend to be
soft, well vascularized, and friable, and tumor spill or spontaneous rupture portends a poor prognosis and compounds the difficulty of treatment decisions.
YES endoscopic biopsy is relatively safe either by direct visualization of a mucosal component or by endoscopic ultrasound guidance.
MEN 2B individuals develop
MTC, pheochromocytomas, megacolon, ganglioneuromatosis, characteristic physical appearance, hypergnathism of the midface, marfanoid body habitus, multiple mucosal neuromas.
After a partial thyroidectomy for papillary thyroid carcinoma, patients are followed with what management
thyroid hormone to suppress TSH
closely followed with ultrasonography.
NO thyroglobulin levels because this is only used after total as a bionary marker of absent or present - it should remain undetectable after total
Primary hyperaldosteronism findings
Conn’s syndrome,
High serum Na
low serum K+,
high urinary K+,
low urinary Na+,
metabolic alkalosis (dumped hydrogen for sodium)
medically refractory hypertension
elevated aldosterone levels.
Due to the lack of autoregulation by renin, a plasma aldosterone to renin ratio greater than 25 is highly suggestive of the
diagnosis. (this means that renin is relatively low compared to aldosterone)
increasing sodium retention (from incr aldo) in exchange for hydrogen in the cortical collecting tubules and potassium in the gut, salivary, and sweat glands.
determine whether a pheochromocytoma is malignant.
There are no reliable histopathologic criteria
Pheochromocytomas are defined as malignant when there are tumor implants distant from the primary mass in NON neuroectodermal tissue:
The axial skeleton, lymph nodes liver, lung, kidney (careful, kidney involvement considered metastatic or considered distant..)
are the most common sites of metastasis.
