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6. What is the cause of steatorrhea in a patient with Crohn’s
disease?
A. Excess excretion of bilirubin and cholesterol in stool
B. Concurrent obstructive primary sclerosing
cholangitis
C. Terminal ileum resections resulting in bile acid and
salts malabsorption
D. Intestinal bacterial depletion resulting in inadequate
CHAPTER 31
bilirubin conjugation
Liver
7. In your patient taking 5 mg of warfarin daily for a prosthetic mitral valve, how might metronidazole treatment
for Clostridium difficile affect their international normalized ratio (INR)?
A. Increase the INR due to cytochrome P-450 isoform
inhibition.
B. Increase the INR due to induction of P-450 isoform.
C. No change, metronidazole does not affect hepatic
metabolism of P-450 isoforms.
D. Reduction of INR due to alterations in intestinal
microflora.
Answer: C
Bile salts are sodium and potassium salts of bile acids derived
from cholesterol by hepatocytes. After synthesis, the primary
bile acids cholic and chenodeoxycholic acid are conjugated
to either taurine or glycine and then secreted into the biliary
system. Approximately 90%–95% of these primary bile salts
and acids are absorbed by active transport at the terminal
ileum, a region commonly affected by Crohn disease, while
the remainder enter the colon and are converted to secondary bile acids (deoxycholic and lithocolic acids) and their
associated salts by resident bacteria. Bile acids and salts
reabsorbed in the terminal ileum are reabsorbed through the
portal circulation, while those lost in the stool are replaced by
hepatic synthesis. The continuous process of secretion of bile
salts in the bile, their passage through the intestine, and their
subsequent return to the liver is termed the enterohepatic
circulation. (See Schwartz 11th ed., p. 1352.)
Answer: A
Many factors can affect drug metabolism in the liver. When
the rate of metabolism of a drug is increased (ie, enzyme
induction), the duration of the drug action will decrease.
However, when the metabolism of a drug is decreased (ie,
enzyme inhibition), then the drug will circulate for a longer
period of time, potentially increasing the effect of the medication. Warfarin is a vitamin K antagonist and therefore reduces
hepatic synthesis of coagulation factors. As metronidazole
inhibits the metabolism of warfarin, the anti-coagulation
effects are increased and the INR may rise. (See Schwartz
11th ed., p. 1352.)
8. Which of the following compounds is not synthesized
predominantly by the liver?
A. Albumin
B. Factor VIII
C. Factor VII
D. Factor II
9. What technique is the most sensitive for the identification of liver lesions?
A. Intraoperative ultrasound
B. Computed tomography (CT) with triple-phase
contrast
C. Magnetic resonance imaging (MRI) with gadoxetate-
based contrast
D. Abdominal ultrasound
Answer: B
The liver is the largest gland in the body, and responsible for
synthesis of the majority of plasma proteins. The liver produces approximately 10 g of albumin per day, and albumin
measurement can therefore be used as a surrogate for liver
synthetic function. This must be interpreted with caution, as
albumin levels can be influenced by a host of factors unrelated
to hepatic function, and albumin’s long half-life (15–20 days)
makes it a poor marker for acute hepatic dysfunction. Most
clotting factors are synthesized predominantly in the liver,
except for factor VIII. Due to this fact the prothrombin time
(PT) and international normalized ratio (INR) may also be
used as markers of hepatic synthetic function. However,
these too should be interpreted with caution as other conditions, including vitamin K deficiency and warfarin use, may
prolong a patient’s PT/INR. (See Schwartz 11th ed., p. 1353.)
Answer: A
Imaging modalities have rapidly improved over the recent
decades, and CT and MRI constitute the mainstays of diagnostic imaging for patients with hepatic pathology. While
routine B-mode and Doppler ultrasound represent excellent
initial screening tests due to the fact that they are both widely
accessible and inexpensive, most patients with pathology
identified on ultrasound will require further imaging. When
characterizing liver lesions by CT scan, contrast enhancement
is necessary for a complete evaluation. Leveraging the dual
blood supply of the liver with the hemodynamics of hepatic
tumors, radiologists are able to selectively enhance the liver
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parenchyma or tumor during the portal venous or arterial
phases of the scan, respectively. Limitations of ultrasound
include incomplete imaging of the liver, most often at the
dome or beneath ribs on the surface, and incomplete visualization of lesion boundaries. Moreover, obesity and overlying
bowel gas also can interfere with image quality. Thus, ultrasonographically detected masses usually require further evaluation by other imaging modalities due to the lower sensitivity
and specificity of ultrasound compared with CT and MRI.
MRI offers advantages over CT in allowing higher soft tissue
contrast and superior depiction of fluid-containing structures
while eliminating the need for ionizing radiation. Development of specialized liver-specific contrast agents, including
ferumoxide and gadoxetate, has led to the development of
MRI that allows characterization of both hepatic structure
and function. While positron emission tomography/computed tomography (PET/CT) is used frequently in the staging and follow-up of patients with metastatic liver lesions, its
role in the diagnosis and management of primary liver lesions
is uncertain. The reported sensitivity of fluorodeoxyglucose
(FDG)-PET/CT for the detection of hepatocellular carcinoma is only 50%–65%. While this has been improved with
development of dual-tracer PET/CT, the clinical benefits of
this modality have yet to be clearly defined. Despite advances
in other imaging modalities, intraoperative liver ultrasound
remains the gold standard. This technique has the ability to
identify 20%–30% more lesions than preoperative imaging,
and it is estimated that approximately 50% of planned surgical resections are influenced by information gleaned from
intraoperative ultrasound. (See Schwartz 11th ed., p. 1357.)
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Liver
10. In a patient without prior liver disease, what is the most
common cause of hepatic encephalopathy occurring
within 26 weeks of severe liver injury?
A. Alcohol in developing nations.
B. Causes are unknown.
C. Hepatitis B, A, and E in the United States.
D. Drug-/toxin-induced (including acetaminophen) in
the United States.
Answer: D
Differences in etiology, management, and patient outcomes
have been described for various regions of the globe. In the
East and developing portions of the world, the most common causes of acute liver failure (ALF) are viral infections,
primarily hepatitis B, A, and E. In these areas, there are a relatively small number of drug-induced cases. In contrast, 65%
of cases of ALF in the West are thought to be due to drugs
and toxins, with acetaminophen (paracetamol) being the
most common etiologic agent in the United States, Australia,
United Kingdom, and most of Europe. In France and Spain,
where acetaminophen sales are restricted, the rate of acetaminophen-induced ALF is quite low. Acetaminopheninduced ALF is also uncommon in South America. The US
Acute Liver Failure Study Group identified several other
causes of ALF, including autoimmune hepatitis, hypoperfusion of the liver (in cardiomyopathy or cardiogenic shock),
pregnancy-related conditions, and Wilson disease. Even with
exhaustive efforts to identify a cause, approximately 20% of all
cases of ALF remain indeterminate in origin. (See Schwartz
11th ed., p. 1361.)
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11. A patient presents with painless jaundice, and is found to
have cirrhosis. They have no history of alcohol abuse, but
do note a history of diabetes mellitus and pseudogout.
They also mention that multiple members of their family have suffered from cirrhosis. What is the most likely
etiology for their cirrhosis?
A. Alcohol abuse
B. Wilson disease
CHAPTER 31
C. α1-antitrypsin deficiency
D. Hemochromatosis
Liver
12. Which of the following clinical observations are associated with the correct pathophysiologic explanations of
cirrhosis?
A. Spider angiomata, palmar erythema, caput medusae
due to portosystemic collateral formation in the setting of portal hypertension
B. Gynecomastia, loss of chest and axillary hair, and tes-
ticular atrophy from chronic spironolactone use
C. Abdominal wall hernias secondary to destruction of
type IV collagen
D. Caput medusae and the presence of the Cruveilhier-
Baumgarten murmur from collaterals between the
portal system and the remnant of the umbilical vein
Answer: D
Chronic hepatitis C infection is the most common cause of
chronic liver disease in the United States. Other etiologies
include alcohol abuse, nonalcoholic steatohepaitis, and autoimmune diseases (primary biliary cirrhosis, primary sclerosing cholangitis, and autoimmune hepatitis). Hereditary
hemochromatosis is the most common metabolic cause of
cirrhosis, and should be suspected if a patient presents with
skin hyperpigmentation, diabetes mellitus, pseudogout, cardiomyopathy, or a family history of cirrhosis. Elevated plasma
ferritin and increased iron saturation levels suggest the presence of iron overload, but these findings also can be seen
in other diseases of the liver. Confirmatory testing can be
achieved by means of genetic testing, liver biopsy, or by assessing the response to phlebotomy. Other uncommon metabolic
disorders leading to cirrhosis include Wilson disease and α1antitrypsin deficiency. (See Schwartz 11th ed., p. 1364.)
Answer: D
The clinical history associated with cirrhosis can include
fatigue, anorexia, weight loss, jaundice, abdominal pain,
peripheral edema, ascites, gastrointestinal (GI) bleeding, and
hepatic encephalopathy. On physical examination, a number
of findings have been described in patients with cirrhosis.
Spider angiomata and palmar erythema are believed to be
caused by alterations in sex hormone metabolism. Finger clubbing may be a consequence of hypoalbuminemia, while the
pathogenesis of white nail beds and Dupuytren contractures
are less well understood. Males may develop features of feminization such as gynecomastia, loss of chest and axillary hair,
and testicular atrophy. Splenomegaly is common, whereas the
cirrhotic liver itself may be enlarged, normal sized, or small.
Ascites and pleural effusion can be seen with fluid accumulation. Abdominal hernias are common with ascites and should
be electively repaired only in patients with well-compensated
cirrhosis; otherwise, the hernia should be repaired at the
time of or after hepatic transplantation. Portal hypertension can manifest as caput medusae and/or the presence of
the Cruveilhier-Baumgarten murmur, a venous hum that can
be auscultated in the epigastrium resulting from collaterals
between the portal system and the remnant of the umbilical
vein. (See Schwartz 11th ed., p. 1364.)
13. Clinically significant portal hypertension is evident
when the _______ exceeds ______ mm Hg.
A. wedged hepatic venous pressure; 10
B. free hepatic venous pressure; 20
C. hepatic venous pressure gradient; 10
D. hepatic venous pressure gradient; 20
Answer: C
Portal hypertension occurs when the pressure in the portal
system is increased due to factors that may be divided into
three categories. Presinusoidal causes of portal hypertension include sinistral/extrahepatic (splenic vein thrombosis,
splenomegaly, splenic AV fistula) and intrahepatic (schistosomiasis, congenital hepatic fibrosis, idiopathic portal fibrosis, myeloproliferative disorder, sarcoid, graft-versus-host
disease) etiologies. Sinusoidal portal hypertension is a consequence of cirrhosis of any etiology. Postsinusoidal hypertension can also be divided into intrahepatic (vascular occlusive
disease) and posthepatic (Budd-Chiari, congestive heart
failure [CHF], inferior vena cava [IVC] webs) etiologies. In
evaluating patients with suspected portal hypertension, an
enlarged portal vein on routine abdominal ultrasonography
may suggest portal hypertension but this is not diagnostic.
Doppler ultrasound allows identification of vascular occlusion
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and the direction of portal venous flow. Computed tomography (CT) and magnetic resonance angiography (MRA) are
useful for evaluating portal venous patency and anatomy.
The most accurate method for measuring portal hypertension is hepatic venography. This procedure introduces a balloon catheter directly into the hepatic vein where free hepatic
venous pressure (FHVP) is measured. The hepatic vein is then
occluded by inflation of the balloon allowing measurement of
the wedged hepatic venous pressure (WHVP). The hepatic
venous pressure gradient (HVPG) may then be calculated by
subtracting the FHVP from the WHVP (HVPG = WHVP −
FHVP). Clinically significant portal hypertension is defined
as HVPG > 10 mm Hg. (See Schwartz 11th ed., p. 1365.)
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14. What is the leading cause of morbidity and mortality
among patients with cirrhosis?
A. Portal hypertension associated variceal bleeding
B. Encephalopathy
C. Development of hepatocellular carcinoma
D. Hepatorenal syndrome
15. How should acute variceal hemorrhage be managed?
A. Balanced blood product resuscitation supplemented
with recombinant factor VIIa
B. Intravenous vasopressin and crystalloid infusion
C. Emergent endoscopic evaluation and variceal
banding
D. Trans jugular intrahepatic portosystemic shunting
(TIPS) followed by variceal banding
Answer: A
The most significant manifestation and the leading cause
of morbidity and mortality related to portal hypertension is
variceal bleeding. Approximately 30% of patients with compensated cirrhosis and 60% of patients with decompensated
cirrhosis have esophageal varices. One-third of all patients
with varices will experience variceal bleeding. Each episode
of bleeding is associated with a 20% to 30% risk of mortality.
If left untreated, 70% of patients who survive the initial bleed
will experience recurrent variceal hemorrhage within 2 years
of the index hemorrhage. (See Schwartz 11th ed., p. 1367.)
Answer: C
Patients with acute variceal hemorrhage should be admitted
to an ICU for resuscitation and management. Blood resuscitation should be performed carefully to reach a hemoglobin
level of approximately 8 g/dL. Overzealous replacement of
blood products and administration of saline can lead to both
rebleeding and increased mortality. Administration of fresh
frozen plasma and platelets can be considered in patients with
severe coagulopathy. Use of recombinant factor VIIa has not
been shown to be more beneficial than standard therapy and
therefore is not recommended at this time.
Vasoactive medications decrease blood flow to the gastroesophageal varices and can be initiated as soon as the diagnosis of variceal bleeding is made. Although vasopressin is the
most potent available vasoconstrictor, its use is limited by its
systemic vasoconstrictive effects that can produce hypertension, myocardial ischemia, arrhythmias, ischemic abdominal
pain, and limb gangrene. Octreotide, a somatostatin analog,
has the advantage that it can be administered for 5 days or
longer, and it is currently the preferred pharmacologic agent
for initial management of acute variceal bleeding. In addition to pharmacologic therapy, endoscopy with variceal band
ligation should be carried out as soon as possible. This combination of pharmacologic and endoscopic therapy has been
shown both to improve the initial control of bleeding and to
increase the 5-day hemostasis rate. TIPS can be performed
in 95% of patients by an experienced interventional radiologist, controls variceal bleeding in >90% of cases refractory to
medical treatment, and should not affect subsequent hepatic
transplantation. (See Schwartz 11th ed., p 1367.)
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16. A 52-year-old man with no travel history, chronic pulmonary obstructive disease, and recurrent diverticulitis
presents with increasing right upper quadrant abdominal pain, fevers, and jaundice. Computed tomography
(CT) imaging notes a single, 5 cm hypodense lesion with
peripheral enhancement in the right lobe of the liver.
What is the best treatment for this patient?
A. Metronidazole and percutaneous drainage
CHAPTER 31
B. Metronidazole
C. Mebendazole
D. Intravenous piperacillin/tazobactam and percutane-
ous drainage
Liver
Answer: D
Pyogenic liver abscesses are the most common liver abscesses
seen in the United States. Patients commonly present with
right upper quadrant pain and fever. Jaundice occurs in up to
one-third of affected patients. They may be single or multiple
and are more frequently found in the right lobe of the liver.
The abscess cavities are variable in size and, when multiple,
may coalesce to give a honeycomb appearance. Approximately
40% of abscesses are monomicrobial, an additional 40% are
polymicrobial, and 20% are culture-negative. The most common infecting agents are gram-negative bacteria. Escherichia
coli is found in two-thirds of cases, and other common organisms include Streptococcus faecalis, Klebsiella, and Proteus
vulgaris. Anaerobic organisms such as Bacteroides fragilis also
are seen frequently. In patients with endocarditis and infected
indwelling catheters, Staphylococcus and Streptococcus species
are more commonly found. Ultrasound examination of the
liver reveals pyogenic abscesses as round or oval hypoechoic
lesions with well-defined borders and a variable number of
internal echoes. CT scan is highly sensitive in the localization of pyogenic liver abscesses, which appear hypodense
with peripheral enhancement and may contain air-fluid levels
indicating a gas-producing infectious organism.
The current cornerstones of treatment include correction
of the underlying cause and intravenous (IV) antibiotic therapy. Empiric antibiotic therapy should cover gram-negative
and anaerobic organisms; percutaneous needle aspiration and
culture of the aspirate may be useful in guiding subsequent
antibiotic therapy. IV antibiotic therapy should be continued for at least 8 weeks and can be expected to be effective in
80% to 90% of patients. Placement of a percutaneous drainage catheter is beneficial only for a minority of patients, as
most pyogenic abscesses are quite viscous and catheter drainage is often ineffective (Fig. 31-8). (See Schwartz 11th ed.,
Figure 31-16, p. 1369.)
FIG. 31-8. Computed tomographic scan of pyogenic liver
abscesses. Multiple hepatic abscesses are seen in a patient after an
episode of diverticulitis. Note the loculated large central abscess as
well as the left lateral segment abscess.
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17. Upon return from New Zealand, a 33-year-old woman
presents with dull right upper quadrant pain and fevers
diagnosed by the presence of echinococcal antigens.
What does the computed tomography (CT) imaging
demonstrate.
A. Multiple, well circumscribed lesions with homog-
enous arterial enhancement and central scar
B. Well-defined low-density round lesions that have
enhancement of the wall, somewhat ragged in
appearance with a peripheral zone of edema in the
left lobe
C. Anteroinferior hypodense lesion with a distinct wall
and ring-like calcifications in the right lobe
D. Asymmetrical nodular peripheral enhancement that
is isodense with large vessels and exhibit progressive
centripetal enhancement fill-in over time in the right
lobe
Answer: C
Hydatid disease is most common in sheep-raising areas,
where dogs have access to infected offal. These include South
Australia, New Zealand, Africa, Greece, Spain, and the Middle East. Hydatid cysts commonly involve the right lobe of
the liver, usually the anterior-inferior or posterior-inferior
segments. Occasionally, the affected patient presents with
symptoms such as dull right upper quadrant pain or abdominal distention.
The diagnosis of hydatid disease is based on the findings of
an enzyme-linked immunosorbent assay (ELISA) for echinococcal antigens, and results are positive in approximately 85%
of infected patients. Ultrasonography and CT scanning of the
abdomen are both quite sensitive for detecting hydatid cysts.
The appearance of the cysts on images depends on the stage
of cyst development. Typically, hydatid cysts are well-defined
hypodense lesions with a distinct wall. Ring-like calcifications of the pericysts are present in 20% to 30% of cases. As
healing occurs, the entire cyst calcifies densely, and a lesion
with this appearance is usually dead or inactive. Daughter
cysts generally occur in a peripheral location within the main
cyst and are typically slightly hypodense compared with the
mother cyst. Magnetic resonance imaging (MRI) of the abdomen may be useful to evaluate the pericyst, cyst matrix, and
daughter cyst characteristics. (See Schwartz 11th ed., p. 1370.)
CHAPTER 31
Liver
18. What is the most common complication following transjugular intrahepatic portosystemic shunt (TIPS)?
A. Encephalopathy
B. Hepatic ischemia
C. Infection
D. Life-threatening hemorrhage
Answer: A
TIPS is a percutaneous procedure used for treatment of
patients who have gastroesophageal varices in the setting of
portal hypertension. It has largely replaced surgical portosystemic shunts due to the fact that it is both safe and effective
while also providing a minimally invasive alternative to major
abdominal surgery. TIPS functions by creating an intrahepatic shunt between the portal and systemic circulation which
causes a reduction in the portal pressure and ultimately in the
blood flow through varices. It is accomplished by endovascular access through the jugular vein to a hepatic vein radical
and subsequent creation of a needle tract that connects it to a
branch of the portal vein. After dilation of the tract, a metallic
stent is deployed to hold the new portosystemic connection
open. Because this shunt reduces first pass metabolism of the
liver, the most common complication of TIPS is encephalopathy which occurs in 25%–30% of patients. Other complications such as hepatic ischemia, infection, renal failure and
hemorrhage may occur, but are rare. (See Schwartz 11th ed.,
p. 1367.)
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19. A patient presents to your clinic for follow up of his
Hepatitis C cirrhosis with mild ascites, an albumin of
2.9 g/dL, creatinine of 2.1 mg/dL, sodium of 121 mEq/L,
international normalized ratio (INR) of 1.6, and bilirubin of 1.9 mg/dL and complete resolution of prior
hepatic encephalopathy.
A. Based upon his clinical presentation and labora-
tory findings, his Model for End-Stage Liver disease
CHAPTER 31
(MELD) score is 26.
B. Summation of his creatinine, INR, and bilirubin indi-
cates he has a Child-Pugh Score in Class B.
C. Based upon clinical and laboratory values, he has a
Child-Pugh Score in Class A.
D. Formulation of his laboratory values indicate his
MELD is 29.
Liver
Answer: D
The MELD is a linear regression model based on three objective laboratory values (INR, bilirubin level, and creatinine
level). It was originally developed as a tool to predict mortality after transjugular intrahepatic portosystemic shunt (TIPS)
but has been validated and used as the sole method of liver
transplant allocation in the United States since 2002. The
MELD formula accounts for objective valuation creatinine,
INR, bilirubin, creatinine with serum sodium subsequently
added to improve sensitivity and specificity.
The Child-Turcotte-Pugh (CTP) score was originally
developed to evaluate the risk of portocaval shunt procedures
performed for portal hypertension and subsequently has
been shown to be useful in predicting surgical risks of other
intra-abdominal operations on cirrhotic. Numerous studies
have demonstrated overall surgical mortality rates of 10%
for patients with class A cirrhosis, 30% for those with class
B cirrhosis, and 75% to 80% for those with class C cirrhosis.
Ranging from 5 to 15, the CTP is calculated based upon a
summation of points derived from the presence of ascites and
encephalopathy, serum bilirubin and albumin levels, as well
as INR. Multiple retrospective studies have demonstrated
that perioperative mortality and morbidity rates correlate
well with the CTP score, and for over 30 years, this measure
had been used as the principal predictor of operative risk
(Table 31-1). (See Schwartz 11th ed., Table 31-4, p. 1365.)
TABLE 31-1 Child-Turcotte-Pugh (CTP) score
Variable 1 Point 2 Points 3 Points
Bilirubin level < 2 mg/dL 2–3 mg/dL > 3 mg/dL
Albumin level > 3.5 g/dL 2.8–3.5 g/dL < 2.8 g/dL
International normalized ratio < 1.7 1.7–2.2 > 2.2
Encephalopathy None Controlled Uncontrolled
Ascites None Controlled Uncontrolled
Child-Turcotte-Pugh class
Class A = 5–6 points
Class B = 7–9 points
Class C = 10–15 points
20. The most common benign hepatic lesion is the:
A. Hemangioma.
B. Simple cyst.
C. Adenoma.
D. Bile duct hamartoma.
Answer : B
While hemangiomas are the most common solid benign
masses found in the liver, the simple hepatic cyst is still the
most common overall. Simple cysts have a prevalence of
approximately 2.8%–3.6%, and are more common in women
by a ratio of 4:1. Cysts are generally found incidentally during abdominal imaging, and small, asymptomatic cysts may
be managed conservatively. Large cysts may begin to cause
abdominal pain, epigastric fullness and early satiety. These
patients may be treated with percutaneous cyst aspiration
and sclerotherapy which is effective in approximately 90%
of patients. For those that fail percutaneous treatment, or
where percutaneous treatment is not available, surgical cyst
fenestration may be considered. If surgical fenestration is performed, the cyst wall should be sent for pathologic analysis to
exclude carcinoma. (See Schwartz 11th ed., p. 1373.)
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21. Which of the following liver lesions carry a significant
risk of spontaneous rupture?
A. Hemangioma
B. Hepatic cyst
C. Adenoma
D. Bile duct hamartoma
22. A patient presents with results from a contrast-enhanced
computed tomography (CT) scan that describe a wellcircumscribed lesion that demonstrates homogenous
enhancement during arterial phase, isodensity on the
venous phase, and a central scar. In general, what would
be the recommended treatment?
A. Reassurance and observation
B. Percutaneous radio frequency ablation
C. Resection
D. Transarterial chemoembolization
Answer: C
Hemangiomas are congenital vascular lesions that may range
in size from <1 cm to ≥25 cm. They are predominantly found
in women, and are generally asymptomatic. Large lesions
may result in discomfort from compression of nearby organs.
Though hemangiomas are at risk for bleeding if they are biopsied, spontaneous rupture is rare. Adenomas, on the other
hand, carry a significant risk for spontaneous rupture with
intraperitoneal bleeding. For this reason, along with their
potential for malignant degeneration, it is generally recommended that hepatic adenomas be resected once discovered.
(See Schwartz 11th ed., p. 1375.)
Answer: A
On contrast-enhanced imaging, an focal nodular hyperplasia (FNH) can be recognized as a well-circumscribed mass
that demonstrates enhancement on the arterial phase and
isointensity on the venous phase. FNH also demonstrates a
characteristic central scar. FNH are solid benign lesions are
similar to adenomas in that they are more common in women
of childbearing age. Unlike adenomas, however, they are not
prone to malignant degeneration or spontaneous rupture. For
this reason, asymptomatic FNHs may be managed conservatively unless adenoma or hepatocellular carcinoma (HCC)
cannot be definitively excluded. Gadolinium-enhanced magnetic resonance imaging (MRI) may allow better visualization
of the fibrous septa extending from the FNH’s central scar.
While FNH and adenomas ma appear similar on computed
tomography (CT) or standard MRI, new MRI contrast agents
like gadobenate dimeglumine (MultiHance) allow superior discrimination between these two lesions (Fig. 31-9).
(See Schwartz 11th, Fig. 31-18, p. 1375.)
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Liver
FIG. 31-9. Computed
tomographic scans showing
classic appearance of
benign liver lesions. Focal
nodular hyperplasia (FNH)
is hypervascular on arterial
phase, isodense to liver on
venous phase, and has a
central scar (upper panels).
Adenoma is hypovascular
(lower left panel). Hemangioma
shows asymmetrical
peripheral enhancement
(lower right panel).
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23. What is the annual conversion rate to hepatocellular
carcinoma (HCC) for patients with cirrhosis?
A. Less than 1%
B. 1%–2%
C. 2%–6%
D. 6%–10%
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24. Which of the following is TRUE in regard to patients
with cholangiocarcinoma?
A. Surgical resection is the treatment of choice for
patients with primary sclerosing cholangitis and
cholangiocarcinoma limited to the common bile
duct.
B. Cholangiocarcinoma is very radiosensitive, there-
Liver
fore external-beam radiation and intravenous
5- fluorouracil constitute destination therapy with
60% 5-year survival.
C. 5-year survival rate following the Mayo Clinic proto-
col and transplantation is 70%.
D. Patients with primary sclerosing cholangitis are not
candidates for the Mayo Clinic protocol.
Answer: C
HCC is the fifth most common malignancy worldwide, and
its risk factors include viral hepatitis, alcoholic cirrhosis,
hemochromatosis, and NASH. Cirrhosis is present in 70% to
90% of patients who develop HCC, and the annual conversion rate from cirrhosis is 2% to 6%. (See Schwartz 11th ed.,
p. 1376.)
Answer: C
Cholangiocarcinoma, or bile duct cancer, is the second most
common primary malignancy of the liver. Cholangiocarcinoma is an adenocarcinoma of the bile ducts; it forms in the
biliary epithelial cells and can be subclassified into peripheral
(intrahepatic) bile duct cancer and central (extrahepatic) bile
duct cancer. Extrahepatic bile duct cancer can be located distally or proximally. When proximal, it is referred to as a hilar
cholangiocarcinoma (Klatskin’s tumor).
In the absence of associated primary sclerosing cholangitis (PSC), surgical resection is the treatment of choice for
hilar cholangiocarcinoma. However, approximately 10% of
patients with cholangiocarcinoma have PSC. Furthermore,
cholangiocarcinoma in the setting of PSC is frequently multicentric and often is associated with underlying liver disease,
with eventual cirrhosis and portal hypertension. As a result,
experience has shown that resection of cholangiocarcinoma
in patients with PSC yields dismal results.
The pretransplant Mayo protocol consists of externalbeam radiation therapy plus a protracted course of intravenous 5-fluorouracil followed by iridium-192 brachytherapy.
Patients then undergo an abdominal exploration with staging. If findings are negative, patients are given capecitabine
for 2 of every 3 weeks until transplantation. Even after restaging with CT/MRI and endoscopic ultrasonography, approximately 15% to 20% of patients will have positive findings for
tumor on abdominal exploration. The 5-year survival rate for
those undergoing transplantation for cholangiocarcinoma at
the Mayo Clinic is approximately 70% and compares favorably with the rate for resection. Current eligibility criteria for
this Mayo Clinic protocol include unresectable hilar cholangiocarcinoma or hilar cholangiocarcinoma with PSC. The
tumor must have a radial dimension of ≤3 cm with no intrahepatic or extrahepatic metastases, and the patient must not
have undergone prior radiation therapy or transperitoneal
biopsy. Many centers have adopted similar protocols with
comparable results. (See Schwartz 11th ed., p. 1377.)
25. A patient undergoes routine cholecystectomy and is
incidentally found to have gallbladder carcinoma without invasion into the muscular layer. Further treatment
should include:
A. No further treatment.
B. External beam radiation with systemic chemotherapy.
C. Reoperation with a segment IVb/V resection and
hilar lymphadenectomy.
D. Reoperation with formal lobectomy and bile duct
resection.
Answer: A
Gallbladder cancer is a rare and aggressive form of biliary
malignancy. In approximately one-third of cases it is diagnosed incidentally following routine cholecystectomy. Treatment for these patients is guided by T stage of the tumor. In
those patients with T1a tumors, as in this question, no further
treatment is necessary. If the tumor invades into the muscular
layer (T1b), reoperation with central liver resection and hilar
lymphadenectomy is recommended. The role for more radical resections is unclear. (See Schwartz 11th ed., p. 1378).
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26. Which of the following is considered a primary determinant of suitability for resection when evaluating a patient
with hepatic colorectal metastases?
A. Number of metastatic tumors
B. Size of metastatic tumors
C. Predicted volume of hepatic remnant
D. Prior therapy
27. Based on the standard Milan criteria, which of the following patients with hepatocellular carcinoma (HCC)
would be eligible for transplantation?
A. One 4.5 cm lesion in segment VI with invasion of the
right portal vein
B. Three lesions confined to the right lobe, with the
largest being 2.5 cm
C. A single, 5.5 cm lesion in segment II
D. Three lesions spread throughout the liver, with the
largest being 3.5 cm
Answer: C
The liver is a common site for metastatic disease in patients
with colorectal disease, and approximately 50% to 60% of
patients diagnosed with colorectal cancer will develop liver
metastases within their lifetime. With the advent of more
aggressive strategies for the management of metastatic colorectal cancer, including improved chemotherapeutic regimens
and expanded use of metastasectomy, the 5-year survival for
patients with isolated metastases to the liver may exceed 30%.
Given these encouraging results, the paradigm for surgical
evaluation and treatment of these patients has shifted to primarily consider the health of the background liver and volume
of the hepatic remnant, and not tumor characteristics like size
and number. (See Schwartz 11th ed., p. 1378.)
Answer: B
Orthotopic liver transplantation (OTL) was first attempted in
the 1980s and 1990s, with initial series reporting 5-year survival rates of 20% to 50%. This led to the introduction of the
Milan criteria which limited eligibility to patients with one
tumor <5 cm or up to three tumors <3 cm and no evidence of
gross intravascular or extrahepatic spread. Adoption of these
guidelines resulted in significant improvement in 5-year survival for patients with HCC treated with OTL. (See Schwartz
11th ed., p. 1380.)
CHAPTER 31
Liver
28. The only FDA-approved systemic chemotherapeutic
agent for hepatocellular carcinoma (HCC) is:
A. Epirubicin.
B. Cisplatin.
C. 5-fluorouracil.
D. Sorafenib.
Answer: D
Though systemic chemotherapy has not proven very effective
in the treatment of HCC, the multikinase inhibitor sorafenib
has been approved for use specifically in these patients. Based
on results of the SHARP trial, there sorafenib demonstrated
a 3-month survival benefit versus placebo. Though these
results are modest, it remains a treatment option for patients
with advanced, unresectable HCC. (See Schwartz 11th ed.,
p. 1381.)
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