Liver: Benign Mass & Cyst

Cystic Mass

Simple Cysts

  • Benign
  • Sx: Abdominal Pain & Nausea
    • Mostly Small & ASx
  • Most Common in Women
  • Most Common in Right Lobe
  • CT Findings:
  • Tx:
    • ASx: Observation, No Serial Imaging
    • Sx: Laparoscopic Wide Unroofing
      • Percutaneous Aspiration Previously Recommended Now Found to Be Ineffective

Polycystic Liver Disease

  • Causes:
    • Associated with Polycystic Kidney Disease (Most Common)
    • Autosomal Dominant Polycystic Liver Disease
      • Autosomal Dominant
      • Not Associated with PCKD or Cerebral Aneurysms
  • Sx: Abdominal Pain & Nausea
    • Mostly Small & ASx
  • Tx:
    • ASx: Observation
    • Sx: Laparoscopic Wide Unroofing
    • Avoid Estrogen

Noninvasive Mucinous Cystic Neoplasm (MCN)/Cystadenoma

  • Most Common in Women
  • Potential for Malignant Transformation
  • Tx: Enucleation
    • If Carcinoma Suspected: Liver Resection

Simple Cyst of the Liver 1

Bile Duct Hamartoma (von Meyenburg Complex)

Basics

  • Small (0.1-1.5 cm) White Lesion in Liver Periphery
  • Benign with No Malignant Potential
  • Often Associated with Polycystic Liver or Kidney Disease
  • Most Common Liver Lesion Seen Incidentally in Laparotomy
  • Tx: None

Hepatic Hemangioma

Basics

  • Congenital Vascular Malformations that Enlarge by Ectasia
  • Most Common Benign Liver Lesion
  • Most Common in Adult Women
    • Increase in Size During Pregnancy or With Estrogen Therapy
  • Most Common in Right Lobe
  • Mostly ASx

CT Findings

  • *See Liver: Mass CT Characteristics
  • Arterial Phase: Peripheral Enhancement
  • Portal Venous Phase: Centripetal Flow
  • Delayed Phase: Isodense Then Hypodense
  • MRI:
    • Smooth, Well-Demarcated & Homogenous
    • Low Signal Intensity on T1
    • Peripheral Nodular Enhancement

Treatment

  • ASx: Conservative
    • If > 5 cm: Repeat Imaging at 6-12 Months
  • Sx: Enucleation or Liver Resection
    • If Bleeding or Giant (> 10 cm): Preoperative Transarterial Embolization

Pediatric Considerations

  • Most Common in Association with Multiple Skin Hemangiomas
  • May Cause AV Shunting & CHF
  • Kasabach-Merritt Syndrome: Consumptive Coagulopathy with Thrombocytopenia

Hepatic Hemangioma. (a) Early Arterial Peripheral Enhancement, (b) Late Homogenous Attenuation 2

Focal Nodular Hyperplasia (FNH)

Basics

  • Hyperplastic Hepatocytes Surrounding a Central Stellate Scar
  • Cause: Disturbance in Blood Flow
    • Most Common in Liver Periphery
  • Second Most Common Benign Liver Lesion
  • Most Common in Adult Women Although Estrogen is Not a Risk Factor
  • Has Kupffer Cells – Takes Up Sulfur Colloid on Liver Scan
  • Mostly ASx

Diagnosis

  • Primarily on Imaging
  • If Uncertain on Imaging: Bx

CT Findings

Treatment

  • Primary Tx: Conservative
  • If Persistent Sx: Resection

FNH. (a) Early Arterial Homogenous Enhancement with Central Scar, (b) Portal Venous Washout, (c) Delayed Phase Isodensity 3

Hepatocellular Adenoma (Hepatic Adenoma)

Basics

  • Benign Epithelial Tumor
    • Small Risk of Malignant Transformation
  • Different from a “Hepatoma” – Hepatoma is Carcinoma
  • Most Common in Adult Women
  • Most Common in Right Lobe
  • No Kupffer Cells – Does Not Take Up Sulfur Colloid on Liver Scan
  • Most (75%) are Symptomatic (Abdominal Pain Most Common)
  • Risk for Rupture, Particularly if > 5 cm
    • No Bx (Bleeding Risk)

Risk Factors

  • Majority Associated with Oral Contraceptive Pills
  • Glycogen Storage Diseases
  • Obesity
  • Anabolic Steroids

CT Findings

  • *See Liver: Mass CT Characteristics
  • Well Circumscribed
  • Variable Attenuation Depending on Calcification, Hemorrhage (Hyperattenuating) or Fat Content (Hypoattenuating)
  • Similar to FNH
  • Arterial Phase: Homogenous Enhancement
  • Portal Venous Phase: Precontrast Density
  • Liver Scan: Cold

Treatment

  • Primary Tx: Stop Oral Contraceptive Pills & Weight Loss
  • ASx & ≤ 5 cm: Repeat Imaging in 6 Months
  • Sx or > 5 cm: Resection
    • If Unresectable: Transarterial Embolization
    • If Ruptured: Emergent Resection (Consider Preoperative Embolization)
  • If Male: Resect All (Higher Risk of Malignant Transformation)

Hepatic Adenoma. (a) Precontrast, (b) Enhancement on Arterial Phase, (c) Gradual Washout on Delayed Phase 4

Liver Scan. (a) FNH (Hot), (b) HCA (Cold) 5

References

  1. Lazoura O, Vassiou K, Kanavou T, Vlychou M, Arvanitis DL, Fezoulidis IV. Incidental non-cardiac findings of a coronary angiography with a 128-slice multi-detector CT scanner: should we only concentrate on the heart? Korean J Radiol. 2010 Jan-Feb;11(1):60-8. (License: CC BY-NC-3.0)
  2. Shimada Y, Takahashi Y, Iguchi H, Yamazaki H, Tsunoda H, Watanabe M, Oda M, Yokomori H. A hepatic sclerosed hemangioma with significant morphological change over a period of 10 years: a case report. J Med Case Rep. 2013 May 28;7:139. (License: CC BY-2.0)
  3. Scialpi M, Pierotti L, Gravante S, Piscioli I, Pusiol T, Schiavone R, D’Andrea A. Split-bolus versus triphasic multidetector-row computed tomography technique in the diagnosis of hepatic focal nodular hyperplasia: a case report. J Med Case Rep. 2014 Dec 14;8:425. (License: CC BY-4.0)
  4. Gore RM, Thakrar KH, Wenzke DR, Newmark GM, Mehta UK, Berlin JW. That liver lesion on MDCT in the oncology patient: is it important? Cancer Imaging. 2012 Sep 28;12(2):373-84.(License: CC BY-4.0)
  5. van den Esschert JW, Bieze M, Beuers UH, van Gulik TM, Bennink RJ. Differentiation of hepatocellular adenoma and focal nodular hyperplasia using 18F-fluorocholine PET/CT. Eur J Nucl Med Mol Imaging. 2011 Mar;38(3):436-40. (License: CC BY-NC-2.0)