Answers

1. c—Both laryngospasm and carpopedal spasm are late manifestations, occurring hours, at least, after circumoral numbness. Hypocalcemia causes hyperreflexia (not hyporeflexia) by increasing neuromuscular excitability. Even if the hypocalcemia is very severe, the heart rate does not change until just prior to death.
    
2. d—Adrenocortical carcinoma is a virulent disease, and it is rarely curable at the time of identification. More than 90% are >6 cm when discovered. Surprisingly, 50% are hormonally active, most commonly producing Cushing's syndrome. Adrenocortical carcinoma is one of the malignancies that seed the biopsy tract, changing a conceivably curable lesion to one that cannot be cured. Thus, fine-needle aspiration is contraindicated in potentially salvageable patients. Carcinoma is one of the indications for open adrenalectomy. If the apparent pseudocapsule of the tumor is breached, malignant cells are spilled into the field, negating any possibility of cure and markedly enhancing the chances of local recurrence. Treatment of these tumors requires wide local resection with significant adjacent tissue (mesocolon, tail of pancreas, posterior stomach, and often, the adjacent kidney).
    
3. a—Gastric polyps are frequent manifestations. They are actually large patches of fundic gland hyperplasia, rather than adenomas, and carry no malignant potential. Duodenal and ileal polyps are, in contrast, adenomatous, and they carry the same very high malignant potential as colonic polyps. Many pathologists consider desmoids to be low-grade malignancies. They consistently recur locally and frequently transition to aggressive soft tissue sarcomas. Familial adenomatous polyposis is associated with a variety of brain tumors, virtually all of which are malignant.
    
4. a—All of the electrolyte concentrations are correct except chloride, which is present in Ringer's lactate at 109 mEq/L. Ringer's is an isotonic crystalloid, whose concentrations approximate those of extracellular fluid.
    
5. b—Anal fissures in young children are common and the result of obsessive parental attempts at toilet training. Hemorrhoids occur much later in life. Polyposis syndromes present with diarrhea at puberty, and rectal bleeding follows in the teens. Juvenile colonic polyps do cause rectal bleeding and usually cure themselves by spontaneous passage, but they are uncommon lesions. Bleeding from Meckel's diverticulum is more aggressive than bleeding with each bowel movement, and it starts much later in life. This lesion is caused by erosion of gastric mucosa contained in the diverticulum.
    
6. e—Adenocarcinoma of the esophagus is exploding in frequency. The incidence is up to 100 new cases/million population. Last year there were almost 15,000 new cases. Initially, the increase was thought to be due to increasing malignant degeneration in Barrett's esophagus, but more recent data suggest that there are more important genetic and epidemiologic factors. Esophageal carcinomas are less frequently squamous cell, and a lower proportion occur in the upper third.
    
7. d—The modified radical neck dissection spares all the listed structures except the posterior triangle lymph-node–bearing areas. The only selective neck dissections that spare these lymph nodes (level V) are the supraomohyoid and lateral neck dissections.
    
8. b—The most common sites of meningiomas are the cerebellopontine angles, cerebral convexities, and the parasagittal and subfrontal regions. Meningiomas are much more common in women, develop from arachnoid cap cells, and recur frequently (10% in 10 years). These lesions invade the brain very late, which frequently makes them curable.
    
9. e—Despite a significant stricture rate, Roux-en-Y choledochojejunostomy is the best procedure at this time. Drainage, which can be done, is not a permanent solution. Removing the clips subjects the duct to the complications of ischemia. Anastomosis of the duct to the duodenum is technically difficult under these circumstances and has a high failure rate. Loop choledochojejunostomy predisposes to cholangitis due to enteroductal reflux.
    
10. a—Nodular melanoma growth begins in a vertical direction, and it is this vertical growth that determines its prognosis. Lentigo maligna and superficial melanomas are superficial and develop vertical growth at a late phase. Retinal melanomas rarely metastasize to lymph nodes because of the absence of lymphatic tissue. When these lesions do metastasize, late, it is to the liver. Acral lentiginous melanomas occur in the subungual areas, skin of the palms and soles, and in African Americans, and these characteristics impair their recognition. Once identified, their behavior is not especially virulent.
     
11. e—Despite their effectiveness, particularly in life-threatening situations, TIPS procedures have a 50% incidence of stenosis due to neointimal hyperplasia. This can generally be corrected by angiographic intervention. TIPS procedures cause encephalopathy in one third of patients, are nonselective shunts and very effective in controlling intractable ascites. In contrast, they are totally ineffective in suprahepatic postsinusoidal causes of portal hypertension.
     
12. b—Eighty percent of amebic abscesses are solitary. They occur primarily in young patients (20–40 years of age), rarely cause jaundice, and overwhelmingly occur in the right lobe of the liver. Amebic abscesses respond well to amebicidal therapy (metronidazole), and may be successfully treated without drainage.