What are the different types of liver masses and their respective treatments?

Types of Liver Masses and Their Treatment

Liver masses are classified into benign and malignant categories, with specific treatment approaches determined by the type of mass, patient characteristics, and disease stage. 1

Common Benign Liver Masses

Hepatic Hemangioma

• Most common benign liver tumor
• Characteristics: Well-defined hypervascular lesion with peripheral nodular enhancement and progressive centripetal fill-in on contrast imaging
• Treatment:
  • Usually requires no treatment if asymptomatic 2
  • Surgical resection only for symptomatic cases with abdominal pain or pressure effects
  • Alternative treatments for symptomatic cases: radiofrequency ablation, transarterial embolization 2

Focal Nodular Hyperplasia (FNH)

• Second most common benign liver tumor
• Characteristics: Well-demarcated lesion with central stellate scar, hypervascularity in arterial phase
• Treatment:
  • No treatment required in asymptomatic patients as there is no risk of malignant transformation 2
  • Surgical resection only for symptomatic cases

Hepatocellular Adenoma (HCA)

• Associated with oral contraceptive use
• Characteristics: Heterogeneous enhancement, intralesional fat, hemorrhage
• Treatment:
  • Discontinuation of oral contraceptives
  • Surgical resection for:
    • Tumors >5 cm due to risk of rupture and bleeding
    • β-catenin activated subtype due to risk of malignant transformation
    • Male patients (higher risk of malignancy) 2

Simple Hepatic Cysts

• Characteristics: Well-defined, thin-walled, anechoic lesions without internal echoes on ultrasound
• Treatment:
  • No treatment for asymptomatic cysts
  • Percutaneous aspiration with sclerotherapy or surgical deroofing for symptomatic large cysts

Malignant Liver Masses

Hepatocellular Carcinoma (HCC)

• Most common primary liver malignancy
• Risk factors: Cirrhosis, chronic hepatitis B/C, alcohol abuse, non-alcoholic steatohepatitis
• Diagnosis: Arterial phase hyperenhancement and washout appearance on portal venous/delayed phases 3
• Treatment based on Barcelona Clinic Liver Cancer (BCLC) staging:
  • Very early/Early stage (BCLC 0/A):
    • Surgical resection for non-cirrhotic patients or Child-Pugh A cirrhosis without portal hypertension
    • Liver transplantation for patients meeting Milan criteria (single tumor ≤5 cm or up to 3 nodules ≤3 cm)
    • Radiofrequency ablation for tumors <5 cm and/or fewer than four in number 3
  • Intermediate stage (BCLC B):
    • Transarterial chemoembolization (TACE) with expected survival of 16-22 months 3
  • Advanced stage (BCLC C):
    • Systemic therapy with sorafenib, extending survival by approximately 2.8 months 4
  • End-stage (BCLC D):
    • Supportive care 3

Intrahepatic Cholangiocarcinoma

• Second most common primary liver malignancy
• Characteristics: Hypovascular mass with peripheral enhancement and delayed central enhancement
• Treatment:
  • Surgical resection with segmental or lobe resection for resectable tumors 1
  • Palliative biliary stenting for unresectable disease causing biliary obstruction 1

Liver Metastases

• Most common malignant liver tumors overall
• Common primary sites: Colorectal, breast, lung, pancreas, gastric
• Treatment:
  • Surgical resection for selected patients with limited disease, especially colorectal metastases
  • For breast cancer liver metastases: systemic chemotherapy/hormonal therapy is primary treatment; surgical resection may be considered for isolated liver metastases without extrahepatic disease 1
  • Locoregional therapies (RFA, TACE) for unresectable disease
  • Systemic therapy based on primary tumor type

Diagnostic Approach

1. Initial imaging:

   • Ultrasound for initial detection
   • Dynamic contrast-enhanced CT or MRI for characterization 1

2. Further characterization:

   • MRI with hepatobiliary contrast agents (e.g., Gd-EOB-DTPA) for indeterminate lesions
   • Contrast-enhanced ultrasound for patients with renal insufficiency 3

3. Biopsy considerations:

   • Rarely required for benign lesions with typical imaging features
   • Avoid for potentially resectable HCC due to risk of tumor seeding (1-3%) 3
   • Consider for indeterminate lesions where imaging is inconclusive

Important Caveats

• In cirrhotic patients, any new liver mass should be considered HCC until proven otherwise 1
• Benign liver lesions are common even in patients with known primary malignancies (30% of cases) 1
• Deep learning algorithms are showing promising results for liver mass classification but are not yet standard of care 1
• Regular surveillance with AFP and ultrasound every 6 months is recommended for high-risk patients (cirrhosis, chronic hepatitis B) 3

The management of liver masses requires a multidisciplinary approach involving hepatologists, radiologists, surgeons, and oncologists to ensure optimal outcomes and minimize unnecessary interventions for benign lesions.