surgical endocrinology

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Surgical Endocrinology University of Virginia Clinical Clerkship in Surgery Peter I. Ellman M.D.

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Page 1: Surgical Endocrinology

Surgical Endocrinology

University of Virginia Clinical Clerkship in Surgery

Peter I. Ellman M.D.

Page 2: Surgical Endocrinology

Plan for Talk

• Review the objectives as outlined by the Lawrence text.

• Discuss the anatomy, physiology, pathophysiology, diagnosis and treatment of thyroid, parathyroid and adrenal gland disorders.

• Discuss the MEN syndromes.

Page 3: Surgical Endocrinology

Objectives for the Thyroid Gland

1. Discuss the evaluation and differential dx of a patient with a thyroid nodule.

2. List the different types of thyroid cancer, their cell types of origin, and the appropriate theraputic strategy for each.

3. Major risk factors for carcinoma of the thyroid gland and prognostic variables that dictate therapy.

4. SX of Hyperthyroidism, DDX and TX

Page 4: Surgical Endocrinology

Objectives for the Parathyroid Glands

1. Understand the role of the parathyroid glands in the physiology of calcium hemostasis.

2. List the causes, symptoms, and signs of hypercalcemia.

3. Know the difference between 1°, 2°, 4° hyperparathyroidism.

4. Discuss the evaluation and ddx of a paitent with hypercalcemia.

5. Understand the management of acute and severe hypercalcemia.

6. Surgical indications for hyperparathyroidism7. Complications of parathyroid surgery.

Page 5: Surgical Endocrinology

Objectives for the Adrenal Glands

1. Describe the clinical features of Cushing’s syndrome and discuss how lesions in the pituitary, adrenal cortex and extraadrenal sites are distinguished diagnostically.

2. Med and surg mgmt of patients with adrenal adenoma, pituitary adenoma causing adrenal hyperplasia, and with ACTH producing neoplasm.

3. Path, clinical features, lab findings, W/U, mgmt. of pt with 1° aldosteronism.

4. Discuss pheochromocytoma, signs and symptoms, W/U, mgmt.5. Discuss adrenal cortical carcinoma, assoicated signs and

symptoms, W/U managment.6. Mgmt. and evaluation of incidentally discovered adrenal mass.7. Causes of adrenal insufficiency in surgical setting, as well as

clinical and laboratory findings (RECENT JAMA ARTICLE)

Page 6: Surgical Endocrinology

Thyroid Anatomy

• Two lobes in neck, connected by isthmus at second tracheal ring.

• Embryologic origin at site of foramen cecum on tongue—migrates ventral to the hyoid bone– why people get thyroglossal duct cyst.

• Arerial supply 2: Superior thyroid artery via the external carotid and Inferior thyroid artery via the Thyrocervical trunk (off the subclavian).

• Venous drainage 3: through the superior, middle and inferior thryoid veins.

Page 7: Surgical Endocrinology

Thyroid Physiology

• Two groups of hormone producing cells– 1: Follicular cells

produce, store and release T4 and T3

– 2: Parafollicular cells secrete calcitonin.

Page 8: Surgical Endocrinology

Follicular cells

• Capture iodide from the circulation and concentrate it and then oxidize it (organification, occuring in the apical membranes of the cells)

• Tyrosine residues of thyrogolbulin are then iodinated by oxidized iodides, forming monoiodotyrosine and diiodotyrosine which then couple to form T4 and T3-which is then stored.

• When thyroid stimulating hormone (TSH) stimulates the thyroid, the iodinated thyroglobulin then is taken into the cell and is hydrolized to T4 and T3-which is then released into the circulation.

Page 9: Surgical Endocrinology

TSH

• Besides stimulating the release of T3 and T4, TSH can stimulate the cell to increase production of thyroid hormones.

• TSH production is stimulated by Thyrotropin-releasing hormone (TRH) which is secreted by the hypothalamus. This intern is controlled by a feedback mechanism. Increased T3 and T4 have a negative feedback mechanism on TRH as well as TSH

Page 10: Surgical Endocrinology

The parafollicular (aka C cells)

• Secrete calcitonin which is stimulated by high serum calcium levels, which inhibits osteoclast activity, which in turn decreased calcium levels.

• Total absence of these cells produces no demonstrable negative physiologic effect!

Page 11: Surgical Endocrinology

Objective T1:W/U of Thyroid Nodule

• Always a thorough H & P (remember for oral exam).– Hx of irradiation to the head or neck?– Family history of MEN syndrome (will get to

this later) – Carefully palpate the thyroid and regional

lymph nodes.– How long has nodule been present? Any

associated pain, hoarseness, dysphagia, dyspnea, or hemoptysis?

Page 12: Surgical Endocrinology

Objective T1:W/U of Thyroid Nodule

• On physical exam:– Nodule should be carefully examined to

assess size, consitency, extension and fixation. Single or multiple?

– Is there cervical lymphadenopathy?– Is there a rapid pulse, tremor, exopthalmos?– Direct laryngoscopy is important in

preoperative evaluation to assess for vocal cord paralysis.

Page 13: Surgical Endocrinology

DDX of thyroid nodule

• Benign – Toxic thyroid adenoma– Cyst– Papillary adenoma– Follicular adenoma

(most common adenoma)

•Colloid (macrofollicular)•Fetal (microfollicular)•Embryonal

– Hürthle cell adenoma

• Malignant– Papillary CA– Follicular CA– Hürthle Cell CA– Medullary CA– Anaplastic CA– Thyroid Lymphoma– Metastatic

Carcinoma to the Throid Gland.

Page 14: Surgical Endocrinology

FNA

• Fine needle aspiration is the single most important study in evaluating a thyroid mass.– Only 3% of patients with a benign dx on FNA have thryoid

cancer, and 85% of nodules identified as malignant on FNA are cancers at resection.

• 68% to 98% sensitive and 56% to 100% specific.• Approx 75% are classified as “benign”, 25% as “suspicious” and

5% as “malignant.

• Follow patients with benign dx closely• Follicular adenomas cannot be distinguished from

follicular carcinoma by FNA and warrants a surgical exploration--most likely total thyroidectomy.– do not do frozen section! It has been shown to be notoriously

inaccurate!)

Page 15: Surgical Endocrinology

Other imaging modalities

• Not required for the routine evaluation of the vast majority of thyroid nodules.

• It is important to try and avoid the use of iondinated contrast materials preperatively.– This can impair postoperative tx.

• Hot vs. Cold nodules.– A technicium thyroid scan may show a “cold” or

hypofunctioning nodule. While it is c/w cancer, it could also be benign solid or cystic nodule that could be diagnosed with or even treated with FNA.

Page 16: Surgical Endocrinology

Use of ultrasound

• Good for determining the size, number and location of thyroid nodules accurately.

• Questionable use as a “screening tool”. Can increase the rate of finding incidentalomas.

Page 17: Surgical Endocrinology

Objective T2: List 7 Thyroid Carcinomas, Cell Types, and Tx.

1. Papillary CA2. Follicular CA3. Hürthle Cell CA4. Medullary CA5. Anaplastic CA6. Thyroid Lymphoma7. Metastatic Carcinoma to the Throid

Gland.

Page 18: Surgical Endocrinology

Papillary CA

• Divided into the papillary, mixed papillary/follicular and follicular variant of papillary.

• Most Common Thyroid Malignancies!

• Arises from Follicular Cells– Histologically associated with fibrosis,

calicifications, squamous metaplasia, psammoma bodies, lymphatic invasion.

Page 19: Surgical Endocrinology

Papillary CA TX

• Tx is somewhat controversial. At the very least pt needs ipsilateral lobectomy and isthmusectomy. Some surgeons recommend total thyroidectomy. It is important to know that you don’t just take out the nodule!

• LND for clinically significant nodal disease.• Surgery is followed by scanning with radioactive

iodine to detect residual normal thyroid tissue as well as metastatic disease (lungs and bones).

Page 20: Surgical Endocrinology

Follicular CA- Overview

• Increased in regions of the world where iodine is deficient.

• Dx of malignancy requires that either vascular or capsular invasion by tumor be demonstrated.

• Again, FNA and Frozen Section cannot be trusted. Dx is deferred pending histologic review.

Page 21: Surgical Endocrinology

Follicular CA—Cell origins

• Come from follicular cells (not surprising)• On histologic exam there is a paucity of

colloid associated with follicular cells.• Extra points for knowing that follicular

carcinomas that demonstrate only minor capsular invasion have a relatively benign course.

• Vascular invasion indicates more aggressive behavior.

Page 22: Surgical Endocrinology

Follicular CA- Tx

• Total thyroidectomy is recommended by many for virtually all patients, particularly those with lesions larger than 4cm. Some surgeons may elect to do just lobectomy and isthmusectomy.

• Adjuvant therapy with radioactive iodine, as with papillary CA

Page 23: Surgical Endocrinology

Hürthle Cell CA-Overview

• Less common than follicular ca and is often considered a subset of follicular ca.

• More aggressive– Higher incidence of metastasis– Lower survivial rate

• Similar difficulties in preoperative dx like follicular cell CA, but there may be a linear relationship between lesion size and malignancy.– In a study of 57 patients, th chance of malignancy when lesions

are >4cm was 65%, and it was 17% when <1cm

• Cell type is still of follicular cell origin.

Page 24: Surgical Endocrinology

Hurthle Cell CA Tx

• For lesions >4cm, total thyroidectomy

• For lesions <1cm, thyroid lobectomy and isthmusectomy, with completion thyroidectomy if the permanent histology proves to be cancer.

• Follow up radioactive iodine??

Page 25: Surgical Endocrinology

Medullary CA (MTC)- Overview

• Slow growing, but aggressive neuroendocrine tumor.– Metastasizes early to lymph nodes, then to liver,

lungs and bones.

• Originates from the parafollicular C cells!!• 80% of pateints with medullary CA have

sporadic MTC, while in 20% people have an autosomal mutation in the RET protooncogene.– RET protooncogene abnormalities are assocated with

the MEN-IIA, MEN-IIB and familial medullary thyroid cancer (FMTC)

Page 26: Surgical Endocrinology

Presentation and Dx of MTC

• FNA can be diagnostic, especially when the slides are assayed for calcitonin and CEA activity. Both are elevated.

• Up to 75% presenting with sporadic MTC have lymph node mets.

Page 27: Surgical Endocrinology

Tx of Sporadic MTC

• Screen for pheochromocytoma and hyperparathyroidism (rule out MEN syndrome)

• Total thyroidectomy with central lymph node dissection (remember that 75%) and ipsilateral modified radical neck dissection.

• No role for radioactive iodine.

Page 28: Surgical Endocrinology

Tx of familial forms of MTC

• Got RET?– Sam Wells, a famously mean surgeon from Duke,

then Wash U. famously showed that there is a role for prophylactic thyroidectomy could be beneficial after DNA testing of patients at risk.

– Children with MEN IIA should undergo thyroidectomy at 5-6 years of age.

• Routine central neck dissection has been advocated, but no lateral LND.

– Children with MEN IIB have the most aggressive form of MTC. Total thyroidectomy should be performed ASAP, preferably before the age of 2.

Page 29: Surgical Endocrinology

Post surgical care for MTC

• Often have persistently high levels of calcitonin.• This often will necessitate repeated aggressive

neck dissection to root out any residual tissue. However, only 38% of these patients will eventually be normalized. These patients often have occult distant mets. Laparoscopic evaluation of the liver has been recently adopted prior to neck dissection.

• Note that this is a slow growing tumor and patients with incurable metastatic disease can often live for decades.

• Radiation may have a role, chemo does not.

Page 30: Surgical Endocrinology

Anaplastic CA

• Rare– BAD NEWS• Patients present with rapidly expanding neck

mass, often with aggressive invasion of local structures, often with airway compromise.

• Derive from de-differentiated follicular adenoma/carcinoma.

• Surgery is often not possible, and thus Chemotherapy and Radiation is the current treatment.

Page 31: Surgical Endocrinology

Thyroid Lymphoma

• Like anaplastic ca, presents as a rapidly enlarging neck mass.

• FNA combined with flow cytometry shows a monoclonal population of lymphocytes.

• Tx is radiotherapy and chemotherapy.

• Studies involving surgical debulking have failed to show any benefit.

Page 32: Surgical Endocrinology

Metastatic Carcinoma to the Throid Gland

• Not as uncommon as you might think.• Autopsy series demonstrate 1% to 24% of

patients who die of extrathyroidal malignancies. 5-7% are clinically significant.

• Most often from Renal Cell CA (50% of cases)

• There is a role for resection of these mets in some patients.

Page 33: Surgical Endocrinology

Objective T3-Risk factors for Thyroid CA

• Hx of irradiation to the head and neck in childhood (used to be for tonsils, enlarged adenoids or thymus, even acne!), nuclear accidents

• Iodine deficiency (goiter)• Female predominance 3:1• More virulent in elderly patients• Genetic (MEN syndromes, FMTC)• Hashimoto’s thyroiditis (lymphoma)• Previous ca (particularly RCC)

Page 34: Surgical Endocrinology

Objective T4 Sx and Tx of Hyperthyroidism

• Causes– Exogenous hormone– Subacute thyroiditis– Postpartum thyroiditis– Iodine induced hyperthyroidism– Struma ovarri– Functional metastatic thyroid carcinoma– Three that are Surgically Treated ARE:

1. Grave’s disease2. Toxic multinodular goiter3. Autonomously functioning toxic adenoma

Page 35: Surgical Endocrinology

Grave’s disease

• Autoimmune disease• Clinical symptoms (of hyperthyroidism)

– Palpitations, sweating, intolerance to heat, irritability, insomnia, nervousness, weigh loss, fatigue

• Signs– Bruit over the gland, tremors, arrhythmias

• Exopthalmos, edema of eyelids, pretibial edema.

Page 36: Surgical Endocrinology

Toxic Multinodular Goiter

• Enlargement of the thyroid glands over a long period of time.

• Treatment is medically initially, but the preferred treatment is surgical.

• In setting of bilateral multiple nodules, total or near total thyroidecomy is indicated.

• If nodules are predominantly on one side, then ipsilateral lobectomy and ithmusectomy are probably adequate.

Page 37: Surgical Endocrinology

Solitary Toxic Adenoma

• Patients presenting with thyrotoxicosis and a dominant thyroid nodule.

• Elevated T3, T4 and a suppressed TSH level.

• Tx is administration of 131I or surgery.• Surgery is recommended for younger

patients with moderate size to large nodules.

• Lobectomy is usually adequate

Page 38: Surgical Endocrinology

Grave’s disease Tx

• Medical for initial treatment.– Antithyroid drugs (propylthiouricil, iodine)– Recurrence is high if drugs are stopped

• Surgical treatment– Bilateral total or near-total thyroidectomy– Pts will now need thyroid replacement for the

rest of their life.

Page 39: Surgical Endocrinology

Parathyroid Gland Anatomy• Paired organs, normally with 2

on the posterior surface of each thyroid lobe.

• Embryologic development from 3rd (inferior parathyroid gland with thymus) and and 4th (superior parathyroid gland and C cell precursors) pharyngeal pouches.

• Art supply from inferior thryoid arteries.

• Superior gland is usually posterior and lateral to the recurrent laryngeal nerve.

• Inferior is anterior and medial to the recurrent laryngeal nerve.

Page 40: Surgical Endocrinology

Ob P1- parathyroid glands and the physiology of calcium hemostasis.

• Synthesize and secret parathyroid hormone, which along with vitamin D maintains calcium hemostasis.

Calcium PTH

Bone resorption, urine phosphorus

Renal resorption

Page 41: Surgical Endocrinology

List the causes, symptoms, and signs of hypercalcemia.

• Stones– Nephrolithiasis

• Bones– Painful resorption of bone

• Moans and Psychatric overtones– Fatigue, depression, confusion

• Abdominal groans– Peptic ulcer and pancreatitis

Page 42: Surgical Endocrinology

Know the difference between 1°, 2°, 4° hyperparathyroidism.

• Primary HyperparathyroidismPTH calcium (normal renal function)–83% parathyroid adenoma, 15% parathyroid hyperplasia, carcinoma is rare 1-2%

• Secondary Hyperparathyroidismpoor renal function calcium, PO4 PTH normal Ca

• Tertiary HyperparathyroidismHyperplastic parathyroids from chronic stimulation continue post renal transplant

Page 43: Surgical Endocrinology

Discuss ddx of a paitent with hypercalcemia.

• Hyperparathyroidism• Malignancy

– Hematologic– PTHrP producer

• Hyperthyroidsm• Multiple myeloma• Sarcoidosis• Milk-alkili syndrome• Vit D or A intoxication

• Paget’s disease• Immobilization• Thiazide diuretics• Addisonian Crisis• Familial hypocalcuric

hypocalcemia• Neonatal severe

hyperparathyroidism.

Page 44: Surgical Endocrinology

Evaluation of Hypercalcemia

• Send off PTH levels to diagnose primary versus other causes.

• 24 hour urine calcium measurement and chloride to phosphate ratio (>33)

• X-rays are diagnostic for Paget’s disease

• EKG– will classically show shortened QT and prolonged PR interval. Check rate for bradycardia.

Page 45: Surgical Endocrinology

Understand the management of acute and severe hypercalcemia.

• Mainstay of management is:

1. admittnance to hospital (severe is considered asymptomatic with >3.2mmol/L, or symptomatic patient)

2. Expand Volume with NSS or LR (500 ml bolus STAT)

3. Diurese with loop diuretics

4. Other meds may be started (bisphosponates, calcitonin, mithramycin ect.)

Page 46: Surgical Endocrinology

Indications for surgery

• Nephrolithiasis, bone disease, and neuromuscular symptoms respond well to surgery.

• Primary hyperparathyroidism due to adenoma is cured surgically by excision of the adenoma. All four glands must be identified though!

• Primary hyperparathyriodism due to parathyroid hyperplasia is treated with subtotal parathyroidectomy (3 1/2) or total parathyroidectomy with autotranspantation into the arm.

Page 47: Surgical Endocrinology

Surgical indications for asymptomatic hyperparathyroidism• On initial evaluation

– Markedly elevated CA– Hx of life threatening

hypercalcemia (??)– Reduced Cr CL.– Nephrolithiasis– Markedly elevated

24hr U Ca– Substantially reduced

bone mass

• Following asymptomatic pt– Pt becomes symptomatic– Ca 1-1.6 mg/100 ml above

normal– Nephrolithiasis– Decline in bone mass– Neuro or psych problems– Pt desire to fix.

Page 48: Surgical Endocrinology

Complications of parathyroid surgery.

• Hypocalcemia

• Persistent hypercalcemia

• Recurrent laryngeal nerve injury

Page 49: Surgical Endocrinology

Adrenal anatomy

• Paired structures living superior to the kidneys. They are flat and triangular, about 5 grams

• Arterial supply (3 each)1. Superior adrenal off inf. phrenic A.

2. Middle adrenal off the aorta

3. Inferior adrenal arising off the enal A.

• Venous supply (one major on each)1. Right adrenal vein drains into vena cava.

2. Left adrenal vein drains into the left renal vein

Page 50: Surgical Endocrinology

Cortex and Medulla

• Cortex- mesodermal in origin– Zona glomerulosa

• Production site of aldosterone

– Zona fasiculata• Production site of cortisol and sex steroids

– Zona reticularis• Production site of cortisol, androgens and estrogens.

• Medulla-ectodermal in origin– Production center of catecholemines epinephrine and

norepinephrine.

Page 51: Surgical Endocrinology

Describe the clinical features of Cushing’s syndrome and discuss how lesions in the pituitary, adrenal cortex and extraadrenal sites are

distinguished diagnostically.

• Cushing’s syndrome (not to be confused with Cushing’s disease!(you know this)– muscle wasting

• Steroidal proteolysis– truncal obesity

• differential insulin and steroid receptors– Htn

• Glucocorticoid effects on the heart, kidneys ect.– ostoporosis

• Steroidal effects on bone growth– infection

• immunosuppression– striae and poor wound healing

• Suppresion of scar contraction and inflammatory response– Hyperglycemia

• decreased peripheral use of glucose and increased gluconeogenesis.

Page 52: Surgical Endocrinology

DDX of Cushing’s Syndrome

• Iatrogenic• Cushing disease (pitutary ACTH excess—

70% of Cushing’s syndrome)• Ectopic ACTH production-15%• Adrenal adenoma or carcinoma- 15%• Micronodular pigmented hyperplasia• Macronodular pigmented hyperplasia• Steroid dependent adrenal hypeplasia

Page 53: Surgical Endocrinology

How lesions in the pituitary, adrenal cortex and extraadrenal sites are distinguished diagnostically

• First confirm that the patient has hypercortisolism.– Start with plasma cortisol on multiple venous

samplings (get at 6am and 8pm) – Diurnal variation in pituitary adenomas and

adrenal tumors.– Can also get 17-OH corticosteroid

measurments in the urine.– Measurment of urinary free cortisol

Page 54: Surgical Endocrinology

How lesions in the pituitary, adrenal cortex and extraadrenal sites are distinguished diagnostically-CONT

Plasma ACTH levels can be helpful in determining

Type of Cushing’s syndrome

Plasma ACTH Level

ACTH after high dose Dexamethasone Test

CRH stimulation test

Pituitary NL to increased

Highly increased cortisol compared to normal

Adrenal Low or undetactable

Ectopic ACTH producing tumor

Increased

Page 55: Surgical Endocrinology

How lesions in the pituitary, adrenal cortex and extraadrenal sites are distinguished diagnostically-CONT

• CT and MRI of head can image pituitary tumors• Ectopic Cushings syndrome represents

approximately 15% of the cases and is more common in men– Most commonly oat cell ca of lung (thus chest film can

be diagnostic), but can also occur with bronchial carcinoids, thymomas, and tumors of the pancreas.

• CT of adrenals is a good first imaging study of the adrenals.– Other fancier tests exist

Page 56: Surgical Endocrinology

Med and surg mgmt of patients with adrenal adenoma, pituitary adenoma causing adrenal hyperplasia, and with ACTH producing

neoplasm

• Medical management– Metyrapone and aminoglutethimide inhibit enzymes of

the adrenal steroidogenic pathway. Not satisfactory for long term.

– Mitotane is a chemotheraputic that is effective 30 to 70 percent of the time in decreasing steroid output in malignant functioning adrenocortical lesions.

– Nonoperative treatment for congenital adrenal hyperplasia (steroid dependent)

• Cortisone acetate is sufficient.• If mineralocorticoid is needed, Florinef works.

Page 57: Surgical Endocrinology

Surgical treatment

• Pituitary Cushings– Transsphenoidal resection for pituitary adenoma is

treatment of choice.– Pituitary irradiation has been shown to effective in

80% of children.

• Adrenal Cushings– Total adrenalectomy of the affected gland

• Ectopic Cushings– Tx is directed towards the underlying neoplasm

secreting ACTH

Page 58: Surgical Endocrinology

Path, clinical features, lab findings, W/U, mgmt. of pt with 1° aldosteronism

Effects of Aldosterone Secretion

Tubular Action Normal amounts Excessive Amts

resorption of Na+

protects against low volume states

•positive sodium balance•hyporeninemia•met alk• htn•hyperglycema•noctura•muscle weakness

resorption of K+

protects against hyperkalemia

Page 59: Surgical Endocrinology

Primary aldosteronism DDX and DX

• DDX – adenoma– Primary hyperplasia of the zona glomerulosa– Adrenal carcinoma

Page 60: Surgical Endocrinology

Dx of Aldosteronism

• Serum tests– Potassium is low, Renin is Low

• Urine tests– Potassium excretion is high– Aldosterone exretion is high

• Confirming tests—plasma and urinary aldosterone suppression tests.– 2,000 ml NSS over 4 hour period should

suppress.

Page 61: Surgical Endocrinology

DX of Aldosteronism cont.

• Very important to distinguish aldosterone producing adenoma from hyperplasia of Zona glomerulosa since surgery only works for one!– Postural stimulation

• Aldosterone and renin are measured in recumbent position and then 2-4 hours after ambulating

– Renin remains suppressed in adenomas

– 18-hydroxycorticosterone is increased in patients with adenomas but remains normal in those with hyperplasia.

– Venous sampling, CT scan may lateralize

Page 62: Surgical Endocrinology

Tx of Aldosteronism

• Medical– Spironolactone

• Inhibits sodium-postassium exchange in the distal tubule, normalizes serum K and may lower blood pressure.

• Surgical– Total adrenalectomy of involved gland– It is important to resore potassium levels

preoperatively.

Page 63: Surgical Endocrinology

Discuss pheochromocytoma, signs and symptoms, W/U, mgmt

• Overview– Funcionally active tumors- producing epinephrine and

norepinephrine– 90% are benign, 10% are malignant

• 10% Rule– Malignant, bilateral, extra-adrenal, multiple, familial, children.

– 90% are found in the adrenal medulla– Of extra-adrenal, most are found in the organs of

Zuckerkandl, extra-adrenal paraganglia, urinary bladder, and mediastinum

Page 64: Surgical Endocrinology

Signs and symptoms of pheo

• Hypertension– 50% sustained

• Can have paroxysms of more severe hypertension superimposed.

– 50% intermittent

• Sweating, headiaches, palpitations, tremor, nervousness, weight loss, fatigue, abdominal or chest pains, polydipsia and polyuria, convulsions

Page 65: Surgical Endocrinology

Workup of pheochromocytoma

• Urinary metanephrines and VMA are elevated in 90% to 95% of cases.

• Fractionated urinary and plasma catecholamine levels can increase the accuracy of the dx to nearly 100%

• CT and MRI (accurate in 95%)

• Scintigraphy and vena cava sampling for that extra hard to find lesion

Page 66: Surgical Endocrinology

Preparation for surgery

• Adrenergic blockade– Preop control of htn– Reduces risks of dramatic pressure swings– Provides vasodilation, allowing restoration of

normal blood volume

• Alpha blockade with Phenoxybnzamine 2 weeks prior to surgery. (40mg/day)

• Beta blockade with propranolol 3 days prior to surgery (40mg/day)

Page 67: Surgical Endocrinology

Operation of pheo

• Arterial and Central venous monitoring

• Transabdomial approach.

• Total adrenalectomy

Page 68: Surgical Endocrinology

Discuss adrenal cortical carcinoma, assoicated signs and symptoms, W/U managment

• Poor prognosis

• 5 year survival rate of 20% to 25%

• Signs and symptoms would be related to adenomatous precursor or asymptomatic.

Page 69: Surgical Endocrinology

Mgmt. and evaluation of incidentally discovered adrenal mass

• Adrenal incidentalomas <5cm do not require resection.

• Negative predictive value for primary adrenal carcinoma in adrenal masses <6cm as measured on CT scans ranges from 96% to 99%.

• Additional tests are not necssary.

Page 70: Surgical Endocrinology

• Causes of postoperative primary adrenal insufficiency include– Autoimmune disease, TB, fungal disease, malignancy,

AIDS, and drug suppression. Hemmorhage is a common cause in the ICU

• Secondary causes (decreased ACTH) include: – suppresion by glucocorticoid therapy, ACTH secreting

tumors, pituitary operation, irradiation, head trauma.• Clinical findings– anorexia, malaise, hypoglycemia,

hypotension:– Low CO and high SVRI or High CO and low SVRI

• Dx is by measuring free cortisol and cosyntropin stim.test• Tx is with fluids and steriods (dexamethasone followed by

hydrocortisone)• Recent study in JAMA

Causes of adrenal insufficiency in surgical setting, as well as clinical and laboratory findings (RECENT JAMA ARTICLE)

Page 71: Surgical Endocrinology

MEN Type I (Wermer’s syndrome)

• Hyperparathyroidism– 90% of patients, mostly hyperplasia of multiple

glands.

• Pituitary tumors– 65%--Usually chromophobe adenomas

• Producing acromegaly, galactorrhea, anmenorrhea, or Cushing’s

• Pancreatic tumors– 80% of cases

• Non-beta islet cell tumors causing the Zollinger-Ellison Syndrome

Page 72: Surgical Endocrinology

MEN IIA (Sipple’s syndrome)

• Hyperparathyroidsim– 60% of patients (shares this in common with

MEN I)

• Medullary thryoid carcinoma– Occurs in ALL PATIENTS

• Pheochromocytomas– Occur in 40%, are usually bilateral,

occasionally are malignant.

Page 73: Surgical Endocrinology

MEN IIB

• Medullary thyroid carcinoma (like II A)• Pheochromocytoma (like IIA)• No hyperparathyroidism• Addition of mucosal neuromas on tongue,

eyelids, lips, pharynx.• Presents at a much earlier age• Marfanoid habitus, kyphosis, pectus excavatum• Hirshprung’s disease

Page 74: Surgical Endocrinology

Objectives for the Thyroid Gland

1. Discuss the evaluation and differential dx of a patient with a thyroid nodule.

2. List the different types of thyroid cancer, their cell types of origin, and the appropriate theraputic strategy for each.

3. Major risk factors for carcinoma of the thyroid gland and prognostic variables that dictate therapy.

4. SX of Hyperparathyroidism, DDX and TX

Page 75: Surgical Endocrinology

Objectives for the Parathyroid Glands

1. Understand the role of the parathyroid glands in the physiology of calcium hemostasis.

2. List the causes, symptoms, and signs of hypercalcemia.

3. Know the difference between 1°, 2°, 4° hyperparathyroidism.

4. Discuss the evaluation and ddx of a paitent with hypercalcemia.

5. Understand the management of acute and severe hypercalcemia.

6. Surgical indications for hyperparathyroidism7. Complications of parathyroid surgery.

Page 76: Surgical Endocrinology

Objectives for the Adrenal Glands

1. Describe the clinical features of Cushing’s syndrome and discuss how lesions in the pituitary, adrenal cortex and extraadrenal sites are distinguished diagnostically.

2. Med and surg mgmt of patients with adrenal adenoma, pituitary adenoma causing adrenal hyperplasia, and with ACTH producing neoplasm.

3. Path, clinical features, lab findings, W/U, mgmt. of pt with 1° aldosteronism.

4. Discuss pheochromocytoma, signs and symptoms, W/U, mgmt.5. Discuss adrenal cortical carcinoma, assoicated signs and

symptoms, W/U managment.6. Mgmt. and evaluation of incidentally discovered adrenal mass.7. Causes of adrenal insufficiency in surgical setting, as well as

clinical and laboratory findings (RECENT JAMA ARTICLE)

Page 77: Surgical Endocrinology

To really get it down

• Have a “friend” pimp you mercilessly on the oral exam questions they have at the end of the chapter (tonight preferably)

Page 78: Surgical Endocrinology

That’s it. Thanks for listening!