General Surgery Rotation

General Surgery: Endocrinology (PEARLS)

The General Surgery End of Rotation Blueprint endocrinology section includes ten topics and comprises 8% of your General Surgery EOR Exam

Adrenal carcinoma Adrenal cortical cancer (ACC) is a rare disease that can also be functional but should be considered on the differential of any adrenal mass, especially tumors larger than 4 cm

  • Less common benign masses include myelolipoma/lipoma, ganglioneuroma, epithelial cyst, and pseudocyst
  • Nearly 4% of abdominal CT scans obtained for another indication demonstrate an incidental adrenal mass
  • Adrenal tumors can also be detected clinically due to manifestations of tumor hormone production
  • Of all adrenal masses, 80% are nonfunctional adenomas, while 15% are functional with laboratory evidence of hormonal overproduction
  • Functional tumors include pheochromocytomasaldosteronoma, and cortisol-producing adenomas. In patients with a previous or present history of malignancy, adrenal metastasis should be considered in the differential

Laboratories

  • Plasma fractionated metanephrines or 24-hour urine metanephrines—must rule out pheochromocytoma for any adrenal mass
  • Serum potassium and aldosterone and plasma renin activity
  • 24-hour urinary-free cortisol or dexamethasone suppression test
  • DHEA-S—high levels can be associated with ACC; virilization is the clinical manifestation of androgen overproduction
  • CT scan - size > 4 cm
  • MRI

Treatment:

  • Adrenal tumors with evidence of hormone production or suspicion of ACC should be considered for adrenalectomy
  • Prognosis for ACC is dependent on treatment at an early stage and complete surgical excision with negative margins
  • Laparoscopic adrenalectomy is NOT recommended for ACC given higher local recurrence rates due to positive or close margins
  • Complete resection often requires en bloc resection of kidney, spleen, pancreas, liver, or IVC for negative margins
  • Overall prognosis remains poor with overall 5-year survival of 25%
Fatigue DDX: Endocrine/metabolic causes of fatigue

Laboratory testing: 

Less commonly indicated

Heat and cold intolerance HypothyroidismHashimoto’s (chronic lymphocytic/autoimmune), previous thyroidectomy/iodine ablation, congenital

  • Cold and heat intolerance, fatigue, constipation, depression, weight gain, bradycardia
  • Labs: TSH- elevated in primary disease. Low T4 (↑ TSH and ↓ Free T4)
  • Hashimoto’s: Antithyroid peroxidase, antithyroglobulin antibodies

Hyperthyroidism (see below) - heat intolerance, palpitations, sweating, weight loss, tremor, anxiety, tachycardia

Hyperparathyroidism PALPABLE neck tumor and hypercalcemia (parathyroid cancer)
Hyperthyroidism Female with heat intolerance, palpitations, sweating, weight loss, tremor, anxiety, tachycardia

  • Graves (autoimmune) - most common cause - diffuse goiter with a bruit, exophthalmos, pretibial myxedema
  • Thyroid storm- Fever, tachycardia, delirium
  • Toxic adenoma, thyroiditis, pregnancy, amiodarone

Diagnosis:

  • TSH (best test): Decreased in primary disease (↓ TSH  and ↑ Free T4), elevated in secondary disease (↑ TSH  and ↑ Free T4)
  • Thyroid radioactive iodine uptake:
    • Graves: Diffusely high uptake
    • Toxic multinodular: Discrete areas of high uptake

Antibodies (Graves): Anti-thyrotropin antibodies (anti-TSH receptor antibodies)

Treatment:

  • Beta-blockers (symptomatic)methimazole/propylthiouracil, radioactive iodine, thyroidectomy
  • Thyroid storm- prompt beta blockers, hydrocortisone, methimazole/propylthiouracil, iodine
  • Thyroidectomy- most likely complication is recurrent laryngeal nerve (hoarseness)

Palpitations Hyperthyroidism (see above) -heat intolerance, palpitations, sweating, weight loss, tremor, anxiety, tachycardia

Pheochromocytoma - recurrent headaches, HTN, sweating, palpitations

Pheochromocytoma Hypertension, diaphoresis (episodic), and palpitations

  • Adrenal neoplasm - catecholamine secreting adrenal tumor - secretes norepinephrine and epinephrine autonomously and intermittently
  • Recurrent headaches, HTN, sweating, palpitations.

Diagnosis:

  • 24-hour catecholamines including metabolites (metanephrine and vanillylmandelic acid)
  • MRI or CT of the abdomen to visualize tumor

Treatment:

  • Resect tumor - complete adrenalectomy
  • Medical treatment preoperative: Alpha blocker (phenoxybenzamine)

Thyroid carcinoma A 35-year-old female with a hoarse voice, solitary cold nodule on thyroid uptake scan, lymphadenopathy, radiation exposure

Most often papillary carcinoma (80%) - think papillary is "popular"

2. Follicular carcinoma: 10%
3. Medullary carcinoma: 5%
4. Hürthle cell carcinoma: 4%
5. Anaplastic/undifferentiated carcinoma: 1% to 2%

Diagnostic studies:

  • Ultrasound is the best initial screen followed by a thyroid uptake scan. Usually normal thyroid function.
  • Microcalcifications, hypoechogenicity, a solid cold nodule, irregular nodule margins, chaotic intranodular vasculature, and a nodule that is more tall than wide.
  • Fine needle biopsy for definitive diagnosis (all lesions >1 cm should be biopsied)
  • TSH, calcium level, CXR

Treatment: Surgical resection

  • Surgical resection with chemotherapy and external beam radiation reserved for anaplastic thyroid cancer.

Thyroid Nodules The diagnostic test of choice for thyroid nodule is Fine Needle Aspiration (FNA)

Evaluation:

  • U/S—solid or cystic nodule
  • Fine Needle Aspirate (FNA) -> cytology 123 I scintiscan (hot or cold nodule)
    • Hot—Increased 123 I uptake = functioning/ hyperfunctioning nodule (non-cancerous) 
    • Cold—Decreased 123 I uptake = nonfunctioning nodule (cancerous) 

History:

  • Neck radiation
  • Family history (thyroid cancer, MEN-II)
  • Young age (especially children)
  • Male > female

Signs:

  • Single nodule
  • Cold nodule
  • Increased calcitonin levels
  • Lymphadenopathy
  • Hard, immobile nodule

Symptoms:

  • Voice change (vocal cord paralysis)
  • Dysphagia
  • Discomfort (in the neck)
  • Rapid enlargement

Tremors Rest Tremors

Postural and Action (Terminal) Tremors

  • Physiologic tremor
  • Exaggerated physiologic tremor (these factors can also aggravate other forms of tremor)
    • Stress, fatigue, anxiety, emotion
    • Endocrine: hypoglycemia, thyrotoxicosispheochromocytoma, adrenocorticosteroids
    • Drugs and toxins: b-agonists, dopamine agonists, amphetamines, lithium, tricyclic antidepressants, neuroleptics, theophylline, caffeine, valproic acid, alcohol withdrawal, mercury (Hatter’s shakes), lead, arsenic, others
  • Essential tremor (familial or sporadic)
  • Primary writing tremor
  • With other CNS disorders
  • With peripheral neuropathy
    • Charcot-Marie-Tooth syndrome (controversial whether to call this the Roussy-Levy syndrome)
    • Variety of other peripheral neuropathies (especially dysgammaglobulinemia)
  • Cerebellar tremor

Kinetic (Intention) Tremor

  • Disease of cerebellar outflow (dentate nucleus and superior cerebellar peduncle): multiple sclerosis, trauma, tumor, vascular disease, Wilson’s acquired hepatocerebral degeneration, drugs, toxins (e.g., mercury), others.

Miscellaneous Rhythmical Movement Disorders

  • Psychogenic tremor
  • Orthostatic tremor
  • Rhythmical movements in dystonia (dystonic tremor)
  • Rhythmical myoclonus (segmental myoclonus—e.g., palatal or branchial myoclonus, spinal myoclonus, limb myorhythmia)
  • Oscillatory myoclonus
  • Asterixis
  • Clonus
  • Hereditary chin quivering
  • Head bobbing with third ventricular cysts
  • Nystagmus
General Surgery: Varicose veins (Prev Lesson)
(Next Lesson) General Surgery: Tremors
Back to General Surgery Rotation

NCCPA™ CONTENT BLUEPRINT

The Daily PANCE and PANRE

Get 60 days of PANCE and PANRE Multiple Choice Board Review Questions delivered daily to your inbox. It's 100% FREE and 100% Awesome!

You have Successfully Subscribed!