How normal is the liver in which the inflammatory type hepatocellular adenoma develops?

Area of Science:

• Hepatology
• Oncology
• Gastroenterology

Background:

• Inflammatory type hepatocellular adenoma (IHCA) is a benign liver tumor subtype, often linked to gp130 or STAT3 mutations.
• IHCA accounts for approximately 40% of all hepatocellular adenomas and is associated with obesity.
• Mutations in IHCA lead to characteristic morphologic changes and increased C-reactive protein (CRP) and serum amyloid-A (SAA) expression.

Purpose of the Study:

• To investigate histomorphological and immunophenotypical alterations in the non-tumorous liver of patients with IHCA.
• To determine if changes in non-tumorous liver tissue differ between tumor-adjacent and distant samples.
• To assess the implications of these non-tumorous liver changes for patient management and follow-up.

Main Methods:

• Analysis of 32 resected IHCA specimens.
• Histomorphological examination of non-tumorous liver tissue (adjacent and distant samples).
• Immunophenotypical analysis, focusing on C-reactive protein (CRP) expression.

Main Results:

• Non-tumorous liver tissue in IHCA cases exhibits abnormalities, including sinusoidal dilatation, single arteries, and minute CRP foci.
• These changes were observed in both tumor-adjacent and distant liver samples, indicating widespread alterations.
• Mild to moderate steatosis was frequent, correlating with a high median Body Mass Index (BMI) of 32.
• Minute CRP foci were more common in cases of multiple IHCA, suggesting potential occult IHCA lesions in the remnant liver.

Conclusions:

• The nonlesional liver in IHCA is not entirely normal and displays distinct histomorphological and immunophenotypical features.
• These findings suggest that IHCA may arise in a liver environment already undergoing changes.
• The presence of abnormalities in the non-tumorous liver has implications for long-term patient follow-up, especially considering the link between obesity and potential malignant transformation.