Master the board step 3

Master the Boards: USMLE Step 3
Treatment
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Best initial therapy: Pneumatic dilation or surgical myotomy
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Pneumatic dilation is done when surgical myotomy is unsuccessful.
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Botulinum toxin injection is used when the patient refuses surgery or
pneumatic dilation.
Basic Science Correlate
Mechanism of Botulinum Toxin
Botulinum toxin inhibits the release of acetylcholine at the neuromuscular
junction. This inhibits nicotinic receptors and relaxes all skeletal muscle.
Esophageal Cancer
Esophageal cancer presents with the following:
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Dysphagia: Solids first, liquids later
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May have heme-positive stool or anemia
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Often found in patients > 50 who are smokers and drinkers of alcohol
• Dysphagia + Weight Loss
= Esophageal pathology
• Dysphagia + Weight Loss
+ Heme-positive stool/
Anemia = Cancer
Diagnostic Testing
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Best initial test: Endoscopy
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If endoscopy is not one of the choices, then barium swallow can be performed.
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Manometry will not be useful, since cancer can only be diagnosed with
biopsy.
CCS Tip: Just order the procedures you think you need on the CCS. Do not wait
for a consult. If you need a consult for a procedure, the computer will tell you.
Treatment
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Best initial therapy: Surgical resection. Surgery is performed if there are no
local or distant metastases.
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Follow surgery with chemotherapy based on 5-fluorouracil.
Rings and Webs
These are also known as “peptic strictures.” They can be caused by the repetitive
exposure of the esophagus to acid, resulting in scarring and stricture formation.
Previous use of sclerosing agents for variceal bleeding can also cause
strictures, and this is why variceal banding is a superior procedure.
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