Abdomen - Liver Flashcards
Hepatic hemangiomas appear macroscopically as…
well-circumscribed, compressible, dark-colored lesions that are typically fed by branches of the hepatic artery.
For hepatic hemangiomas, is biopsy indicated? What is the recommended imaging test?
No biopsy d/t hemorrhage risk. MRI can confirm dx.
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.
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.
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.
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.
What can contribute to hepatocellular carcinoma (HCC) development?
Inflammation, necrosis, fibrosis, and ongoing regeneration
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.
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.
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.
Who are FNH usually found in?
females (8:1) and in the third to fifth decades of life
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.
More than 75% of primary malignant liver tumors are…
HCC
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.
On imaging, hemangiomas are characterized by…
peripheral nodular enhancement on arterial phase followed by progressive centripetal fill-in on portal venous phase.
On imaging, FNH lesions show…
bright arterial enhancement on arterial phase, except for a commonly seen central scar that remains hypoattenuating.
On imaging, hepatic adenomas show…
enhancement on arterial phase but do not demonstrate washout on delayed venous phase (a sign pathognomonic for HCC).
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.
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.
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.
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.
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.
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).
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.
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.
Systemic therapy options for HCC include…
chemotherapy with sorafenib and immunotherapy.
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.
What tumor markers support the diagnosis of cholangiocarcinoma as opposed to HCC?
Elevated CEA and CA 19-9 but normal AFP
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.