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Flashcards in Abdomen - Liver Deck (73):
1

Hepatic hemangiomas appear macroscopically as...

well-circumscribed, compressible, dark-colored lesions that are typically fed by branches of the hepatic artery.

2

For hepatic hemangiomas, is biopsy indicated? What is the recommended imaging test?

No biopsy d/t hemorrhage risk. MRI can confirm dx.

3

Focal nodular hyperplasia (FNH) lesions present macroscopically as...

nonencapsulated, lobulated tumors w/ similar lighter color than surrounding liver. Lesions greater than 5 cm more commonly show a central fibrous scar. This feature, when present radiographically and/or pathologically, is pathognomonic for FNH.

4

Hepatic adenomas present macroscopically as...

yellow-tan, well-circumscribed, round lesions. The absence of bile ducts from these lesions on frozen and/or permanent section can safely differentiate them from FNH lesions, with significant implications for further management.

5

Hepatic adenomas are strongly associated with...

high-estrogen states, such as pregnancy and oral contraceptive use. Chronic androgen steroid therapy and anabolic steroid use can also promote the formation and growth of these lesions. Discontinuation of these hormones is expected to induce tumor regression.

6

What are considered risk factors for development and progression of hepatic adenomas?

Congenital diseases, such as glycogen storage diseases, and related metabolic syndrome manifestations, such as diabetes mellitus, dyslipidemia, and obesity.

7

What can contribute to hepatocellular carcinoma (HCC) development?

Inflammation, necrosis, fibrosis, and ongoing regeneration

8

Contrast the development of HCC in hep B and hep C patients.

In patients with hepatitis B virus (HBV), HCC can develop in livers that frankly are not cirrhotic. By contrast, in patients with hepatitis C virus (HCV), HCC invariably presents in the setting of cirrhosis.

9

How should you approach a liver mass in a cirrhotic patient?

Should be viewed as HCC until proven otherwise. Typically, hepatomas need to be differentiated from a regenerative nodule or cholangiocarcinoma, using cross-sectional imaging (computed tomography [CT] or MRI), alpha-fetoprotein (AFP) levels, and possibly biopsy.

10

What age range are hemangiomas found in? How are they often found?

Can occur at any age, but most are diagnosed in individuals 30 to 50 years of age. They are often found incidentally in asymptomatic patients.

11

Who are FNH usually found in?

females (8:1) and in the third to fifth decades of life

12

Who are hepatic adenomas usually found in?

Approximately 90% of patients with hepatic adenomas are females from 15 to 45 years of age with a history of oral contraceptive use.

13

More than 75% of primary malignant liver tumors are...

HCC

14

What is the first step in differentiating liver masses?

Cystic and solid masses should first be differentiated. Most common cystic liver lesions are simple hepatic cysts, polycystic liver disease, and biliary cystadenomas. The latter represent premalignant lesions and warrant surgical resection.

15

On imaging, hemangiomas are characterized by...

peripheral nodular enhancement on arterial phase followed by progressive centripetal fill-in on portal venous phase.

16

On imaging, FNH lesions show...

bright arterial enhancement on arterial phase, except for a commonly seen central scar that remains hypoattenuating.

17

On imaging, hepatic adenomas show...

enhancement on arterial phase but do not demonstrate washout on delayed venous phase (a sign pathognomonic for HCC).

18

What is the second most common primary liver cancer? How does it appear on imaging?

Intrahepatic cholangiocarcinoma typically appears as a low-attenuation mass with minor peripheral enhancement, capsular retraction, and dilatation of the bile ducts distal to the mass.

19

Compare anatomic and nonanatomic liver resections.

Anatomic resections usually involve one to six contiguous hepatic segments, whereas nonanatomic resections involve resection of the lesion with a surrounding margin of uninvolved tissue irrespective of segmental anatomic boundaries.

20

What is the difference between a right and left hepatectomy?

Right hepatectomy involves resection of segments V to VIII, whereas left hepatectomy involves resection of segments II to IV.

21

What is an extended right hepatectomy? Extended left hepatectomy?

Extended right hepatectomy (or right trisegmentectomy) involves resection of all segments lateral to the umbilical fissure (IV-VIII, and sometimes I), whereas extended left hepatectomy (or left trisegmentectomy) includes resection of the left lobe plus the anterior sector of the right liver (segments II-IV, V, and VIII), with or without segment I.

22

To reduce bleeding during a hepatectomy, the central venous pressure should be kept at what ideally?

ideally < 5 cm H2O. Following completion of liver transection, intravascular volume may be restored.

23

What maneuver can be used to reduce bleeding during liver transection?

The Pringle maneuver (clamping of the hepatoduodenal ligament). This should be done in an intermittent fashion (eg, 10-15 minutes of clamping followed by 5 minutes without clamping).

24

What are contraindications to liver resection for HCC?

The presence of metastatic disease and Child C or advanced Child B cirrhosis are contraindications to liver resection for HCC. Relative contraindications include the presence of multiple liver tumors (multifocal HCC) and macroscopic vascular invasion (tumor thrombus) in branches of the portal vein or the hepatic veins.

25

Liver-directed therapy options for HCC include... What are timing options for applications of these therapies?

Thermal ablation, transarterial chemoembolization (TACE), radioembolization. These treatments can be applied preoperatively to potentially downstage the tumor and permit resection or transplantation, and they can be used for patients who are not candidates for operative management.

26

Systemic therapy options for HCC include...

chemotherapy with sorafenib and immunotherapy.

27

A 34-year-old woman is referred for further evaluation of a new 5-cm liver lesion incidentally diagnosed 1 month ago on abdominal ultrasound. The patient is asymptomatic. She is currently taking oral contraceptive pills. What is your approach to evaluating this patient further?

Contrast-enhanced cross-sectional imaging (CT or MRI) is needed to confirm the diagnosis (hepatic adenoma). Normal AFP levels support the clinical suspicion of a benign hepatic mass lesion. Surgery is recommended for lesions larger than 5 cm and/or those located on the surface of the liver, especially if the patient desires future pregnancy.

28

What tumor markers support the diagnosis of cholangiocarcinoma as opposed to HCC?

Elevated CEA and CA 19-9 but normal AFP

29

A CT liver protocol reveals a single 4-cm liver mass with peripheral enhancement, capsular retraction, and biliary dilatation peripheral to the mass. Carcinoembryonic antigen (CEA) is 78 ng/mL, cancer antigen 19-9 (CA 19-9) is 85 U/mL, and AFP is less than 1 mg/mL. Biopsy of this mass reveals adenocarcinoma. What is your approach to evaluating this patient further?

Positron emission tomography scan, esophagogastroduodenoscopy, and colonoscopy to rule out an upper or lower gastrointestinal primary tumor as a source of a potential liver metastasis. Treatment for a localized intrahepatic cholangiocarcinoma is partial hepatectomy. Portal lymph node dissection is also warranted for staging purposes.

30

A 73-year-old man with chronic HCV and cirrhosis presents with newly diagnosed liver masses. Triphasic liver CT reveals four liver lesions in both lobes of the liver (maximum size 5.5 cm), demonstrating enhancement on arterial phase and washout on delayed phase. There is no extrahepatic disease. AFP is 278 ng/mL. What is your approach to further management of this patient? What are her options?

Liver biopsy is not necessary, given the pathognomonic enhancement pattern of the lesions on CT, the elevated AFP, and the history of HCV cirrhosis. Furthermore, needle biopsy can lead to seeding of the needle tract by HCC. Given the multifocality and bilobar distribution of the tumors, the patient is not a candidate for surgical resection. The patient is not a candidate for liver transplantation, because his tumors do not satisfy the Milan criteria (one tumor < 5 cm in size or two to three tumors > 3 cm). It is necessary to perform further laboratory workup, calculate the Child-Pugh and MELD scores, interpret the results appropriately, and discuss them with the patient. TACE and sorafenib are the most appropriate first-line treatment options for this patient.

31

Broad causes of indirect hyperbilirubinemia

increased production

increased hepatic uptake

impaired conjugation

32

Broad causes of direct hyperbilirubinemia

defect of canalicular organic anion transport

defect of sinusoidal reuptake of conj bilirubin

extrahepatic cholestasis 

intrahepatic cholestasis

33

What can cause increased bilirubin production (leading to indirect hyperbilirubinemia)?

extra/intravascular hemolysis

extravasation of blood into tissue (hematoma resorption)

Wilson's

dyserythropoietic states

34

What can cause impaired bilirubin uptake leading to indirect hyperbilirubinemia?

heart failure

portosystemic shunts

rifampin, probenecid

35

What can cause impaired bilirubin conjugated leading to indirect hyperbilirubinemia?

Crigler-Najjar

Gilbert

neonates

hyperthyroid

chronic hepatitis

advanced cirrhosis

36

What is a defect in organic anion transporter leading to direct hyperbilirubinemia?

Dubin-Johnson syndrome

37

What is a defect in the sinusoidal reuptake in conjugated bilirubin leading to direct bilirubinemia?

Rotor syndrome

38

How do you workup jaundice?

  • H&P - meds, abdominal procedures, drinking, IVDU, travel
  • Determine indirect vs direct: LFTs, INR, albumin
    • ALP/GGT is in biliary tree, INR correcting w/ vit K - poor absorpx
    • If unconjugated, needs medicine workup
    • If conjugated, needs imaging - RUQ US/CT then ERCP/MRCP

39

What are some post-surgical causes of prehepatic jaundice (indirect hyperbilirubinemia)?

hemolytic transfusion reaction, cardiopulmonary bypass, hematoma resorption, 

40

What are some surgical causes of intrahepatic disruption leading to hyperbilirubinemia?

TPN

hypoxia/ischemia

sepsis

41

What are some postop post-hepatic causes of hyperbilirubinemia?

stricture

bile leak

acalculous cholecystitis

42

Causes of pyogenic liver abscess

  • contiguous from biliary infection
  • portal vein if gut source
  • hepatic artery if systemic source of infection
  • direct trauma 
  • adjacent organs

43

In pyogenic liver abscess, history of *________ leads to suspicion of what etiology?

tropical travel

amebic hepatic abscess

44

In pyogenic liver abscess, history of *________ leads to suspicion of what etiology?

diverticulitis

GI source through portal vein

45

In pyogenic liver abscess, history of *________ leads to suspicion of what etiology?

IVDU, shady tattoo places

bacteremic source (through hepatic artery)

46

How do you treat amebic pyogenic liver abscess?

metronidazole 750 TID x10 days

47

An immigrant from Turkey presents with a complaint of chronic right upper quadrant pain. Ultrasonography shows a cystic mass in the liver. How do you proceed?

Obtain an enzyme-linked immunosorbent assay (ELISA) for Echinococcus.

Begin treatment with albendazole.

If symptoms do not disappear after 4 weeks of oral albendazole therapy, begin PAIR (puncture, aspirate, inject with scolicidal agent, reaspirate).

If PAIR fails, do surgical resection. 

48

A woman receives a bone marrow transplant for acute myeloid leukemia. Two months after the procedure, she presents with right upper quadrant pain, left shoulder tip pain, and fever. How do you proceed?

Obtain an abdominal CT and liver function tests.

Recognize hepatosplenic candidiasis via multiple small lesions in the liver and/or spleen.

Perform a CT-guided aspiration of the liver lesion and begin antifungal therapy.

49

One hour after returning from a percutaneous drainage and catheter insertion procedure, a man's blood pressure is 100/65 mm Hg and heart rate is 115 bpm. What is your immediate management strategy for this patient?

Begin immediate coverage with broad-spectrum antimicrobial therapy.

Request a "stat" Gram stain to ensure a pyogenic etiology.

Support organ function/dysfunction with intravenous hydration, increased monitoring, and serial clinical examinations.

50

Two weeks after undergoing an endoscopic retrograde cholangiopancreatography and endoscopic stent placement for obstructing hilar cholangiocarcinoma, a patient presents with fever and chills. How do you proceed?

Start intravenous antibiotics and hydration for sepsis - cholangitis on ddx (pancreatitis also)

Obtain liver function tests and a CT with contrast to confirm the position of the stent.

Ensure drainage of all segments of the liver and rule out pyogenic abscesses.

51

An intravenous drug addict who was recently treated for endocarditis presents with right upper quadrant pain, elevated liver function tests, and fever. How do you proceed?

Obtain abdominal ultrasonography and/or CT and repeat blood cultures.

Treat with antibiotics appropriate for the same organism (Staphylococcus) from the heart valve.

Perform CT-guided aspiration for all lesions greater than 2 cm.

52

In a patient who is persistently unwell despite multiple percutaneous procedures (multiple drains and/or increasing drain sizes), what are the indications for operative management?

  • Operative interventions are extremely uncommon, particularly for pyogenic abscesses.
  • Surgery is indicated for patients who need surgical correction of their underlying pathology/etiology. 
  • Surgery also indicated for patients who fail conservative management in the context of liver abscesses that have ruptured into the peritoneal cavity. 
  • Laparoscopic approaches to drainage are reasonable depending on the location of the abscess and adjacent structures.

53

A man with a previous history of pyogenic hepatic abscesses that were percutaneously drained 2 years previously presents with similar symptoms. What is your differential diagnosis for the etiology and your management strategy?

Recurrent hepatic abscesses are unusual - suspect another dx.

Recurrent abscesses tend to be caused by the same organisms that generated the initial abscess.

Pyogenic recurrence rates depend on the specific microorganism.

54

How do you define and treat small liver abscesses?

Long-term antibiotics alone without drainage may be a viable option for patients presenting with small liver abscesses (less than 5 cm).

55

What is the role of percutaneous drainage for small hepatic abscesses?

Percutaneous needle aspiration of small lesions may be necessary for culture and isolation of bacteria for targeted antibiotic therapy.

56

Are antibiotics required for treatment of hepatic abscesses?

Drainage of abscess along with IV antibiotic therapy is optimal treatment for pyogenic abscesses, especially those greater than 5 cm.

57

What subsequent therapy is required for patients with liver abscesses suspected to have a biliary origin?

biliary decompression via endoscopic, percutaneous, or surgical means may be necessary

58

Given a patient with a pyogenic abscess, be able to identify indications for surgical drainage.

Almost never primary treatment unless... 

In patients with intraperitoneal rupture of the abscess

In patients presenting with septic shock where the liver abscess is identified as the source

When appropriate resources are not available for percutaneous drainage (ie, an experienced interventional radiologist)

Surgical drainage is indicated as a second line option in patients with persistent hepatic abscess(es) who have failed multiple percutaneous drainages. Use IOUS. 

59

Given a patient with an amebic abscess, be able to independently identify indications for percutaneous drainage.

  • Due to the efficacy of metronidazole for curing amebic liver abscesses, aspiration or drainage is hardly ever necessary.
  • Serology is inconclusive and there is no way to discern if the liver lesion in question is a pyogenic vs amebic abscess.
  • Antiamebic drug (ie, metronidazole) is contraindicated (eg, in pregnancy), and no other drugs are available.
  • The liver abscess is secondarily infected with bacteria. This occurs approximately 15% of the time.
  • Patient has persistent symptoms despite antiamebic treatment. This may be the same as in co-infection of the liver abscess. 

60

Given a patient with an amebic abscess, be able to identify indications for surgical drainage.

  • Peritonitis from rupture of an amebic abscess
  • Complications arising from the rupture
  • Fistulas to the stomach, duodenum, and colon have been reported from amebic rupture and invasion into surrounding hollow viscera.
  • Patients who have ongoing sepsis despite adequate treatment of the amebic abscess may require an operation.

61

What pathologic entities might be encountered as incidental findings during a laparotomy?  Describe the gross appearance of each, as it might appear on the surface of the liver.  

  • Hemangioma: soft purple.
  • Cyst: clear fluid or bile stained.
  • Adenoma: soft, whitish-yellow.
  • Focal nodular hyperplasia: firm, tan colored.
  • Metastatic carcinoma: hard, white with small vascular marking.
  • Hamartoma: most common incidental lesion – small, firm, white.
  • Hepatoma: various forms – usually scirrhous, white.

62

A patient with colon cancer had preoperative CT scanning that showed a possible lesion measuring 1.5 cm in the right lobe of the liver.  At the time of laparoscopy, no lesion is visible on the liver surface. What will you do?

  • Use intraoperative ultrasonography to determine if there is a lesion in the right lobe.
  • If a lesion is present, perform an ultrasound-guided core needle biopsy.
  • If no lesion is seen, no specific action is necessary.  CT does have a small false-positive rate.

63

Describe the technique for laparoscopic biopsy of surface lesions of the liver.

Lesions on the liver edge are amenable to harmonic scalpel or stapling to create a wedge biopsy.  Cautery can provide necessary hemostasis.

For surface lesions not at the liver edge, a cup forceps biopsy may be performed.  If the intent is to completely remove the lesion, scissors can be used, followed by cautery.  An excisional biopsy should include a margin around the lesion, which can be marked on the liver surface with cautery. 

64

Describe the technique for open biopsy of surface lesions of the liver.  

Small lesions on the surface of the liver may be excised with a knife, followed by cautery to seal the bleeding surfaces.

Using a knife to excise the lesion will not introduce thermal artifact into the biopsy specimen.

65

After performing a laparoscopic core needle biopsy of the liver, blood gushes from the biopsy site. How will you manage this?

  • Apply pressure to the liver, preferably from two directions to compress the liver in the area of the biopsy site.
  • Do not just cauterize the surface, since bleeding may continue deep within tract.
  • Try injecting fibrin glue into the tract.
  • Open the abdomen as necessary.
  • For refractory bleeding, mobilize the liver to get better pressure, or apply a Pringle maneuver.

66

Given a patient undergoing exploratory laparotomy for liver resection, the chief resident can describe the uses of intraoperative ultrasound, including:

a. Mapping vascular structures,

b. Identification and measurement of all lesions,

c. Ensuring the resection margin is adequate, and

d. Ensuring adequate inflow and outflow of the remaining liver.

67

During an intraoperative ultrasound in a patient with a preoperative diagnosis of a solitary liver metastasis in segment 8, an additional 1 cm lesions was identified in segment 7. What would be the next steps and how would this change the operative plan?

biopsy confirmation

intraoperative findings might change the plan to additional or larger resection

need to inform the family if possible

68

 

A 34-year-old woman is referred for further evaluation of a new 5-cm liver lesion incidentally diagnosed 1 month ago on abdominal ultrasound. The patient is asymptomatic. She is currently taking oral contraceptive pills. What is your approach to evaluating this patient further?

  • The most common benign liver lesion in a young woman taking oral contraceptive pills is hepatic adenoma.
  • Contrast-enhanced cross-sectional imaging (CT or MRI) is needed to confirm the diagnosis.
  • Hepatic adenomas are expected to regress after discontinuation of oral contraceptive pills.
  • Normal AFP levels support the clinical suspicion of a benign hepatic mass lesion.
  • Hepatic adenomas, if peripheral in the liver or large, could be complicated by rupture and/or malignant degeneration to HCC (especially if > 5 cm). Typically, surgery is recommended for lesions larger than 5 cm and/or those located on the surface of the liver, especially if the patient desires future pregnancy.

69

A 50-year-old man with chronic HBV and good underlying liver function presents for evaluation of a recently diagnosed liver mass. The patient currently reports weakness, anorexia, and an unexplained 10-lb weight loss over the past 1 month. A CT liver protocol reveals a single 4-cm liver mass with peripheral enhancement, capsular retraction, and biliary dilatation peripheral to the mass. Carcinoembryonic antigen (CEA) is 78 ng/mL, cancer antigen 19-9 (CA 19-9) is 85 U/mL, and AFP is less than 1 mg/mL. Biopsy of this mass reveals adenocarcinoma. What is your approach to evaluating this patient further?

  • HCV and HBV infections are risk factors not only for HCC but also for intrahepatic cholangiocarcinoma.
  • Elevated CEA and CA 19-9 but normal AFP supports the diagnosis of cholangiocarcinoma as opposed to HCC.
  • The patient needs to be evaluated with a positron emission tomography scan, esophagogastroduodenoscopy, and colonoscopy to rule out an upper or lower gastrointestinal primary tumor as a source of a potential liver metastasis.
  • Treatment for a localized intrahepatic cholangiocarcinoma is partial hepatectomy. Portal lymph node dissection is also warranted for staging purposes.

70

A 73-year-old man with chronic HCV and cirrhosis presents with newly diagnosed liver masses. Triphasic liver CT reveals four liver lesions in both lobes of the liver (maximum size 5.5 cm), demonstrating enhancement on arterial phase and washout on delayed phase. There is no extrahepatic disease. AFP is 278 ng/mL. What is your approach to further management of this patient?

  • Liver biopsy is not necessary, given the pathognomonic enhancement pattern of the lesions on CT, the elevated AFP, and the history of HCV cirrhosis. Furthermore, needle biopsy can lead to seeding of the needle tract by HCC.
  • Given the multifocality and bilobar distribution of the tumors, the patient is not a candidate for surgical resection.
  • The patient is not a candidate for liver transplantation, because his tumors do not satisfy the Milan criteria (one tumor < 5 cm in size or two to three tumors > 3 cm). 
  • It is necessary to perform further laboratory workup, calculate the Child-Pugh and MELD scores, interpret the results appropriately, and discuss them with the patient. 
  • TACE and sorafenib are the most appropriate first-line treatment options for this patient.

71

In a patient presenting with a pyogenic abscess, what are the key steps in treatment?

  • IV antibiotics that cover microaerophilic streptococci, gram-negative bacilli, and anaerobes
  • If the abscess is big enough and amenable to drainage, either a percutaneous catheter or needle procedure should be undertaken.
  • The underlying cause of the abscess should be investigated. Resolution of the primary cause is necessary to resolve all ongoing infections.

72

What are the indications for surgical drainage procedure for pyogenic abscess?

  • Surgical intervention as the first line therapy is indicated in patients with intraperitoneal rupture of the abscess
  • Intervention indicated in those patients presenting with septic shock where the liver abscess is identified as the source and/or appropriate resources (ie, an experienced interventional radiologist) are not available for percutaneous drainage.
  • In patients with persistent abscess(es) with symptoms who have failed multiple perc drains, surgery may be indicated.
  • Laparoscopic approach is preferred over open approach unless the patient has contraindications to laparoscopy.

73

Is percutaneous or surgical intervention indicated in amebic abscesses?

  • With the success of metronidazole for treatment, invasive interventions are hardly ever indicated in amebic abscesses.
  • Percutaneous needle aspx considered if the dx is uncertain, if the medication is contraindicated or not efficacious.
  • Surgical intervention may be necessary if the amebic abscess ruptures causing peritonitis or due to complications that may arise from the rupture, such as fistula formation to nearly hollow viscus.