Morphologic and Molecular Findings in Myxoid Hepatic Adenomas

Area of Science:

• Hepatology
• Oncology
• Molecular Pathology

Background:

• Myxoid hepatic adenomas (MHAs) are rare hepatic adenoma subtypes.
• Characterized by extracellular myxoid material deposition between hepatic plates.

Purpose of the Study:

• To investigate the clinicopathological and molecular features of myxoid hepatic adenomas.
• To assess the malignant transformation potential of MHAs.

Main Methods:

• Retrospective analysis of 9 MHA cases.
• Histopathological examination and molecular profiling (gene mutation analysis).

Main Results:

• MHAs occurred in middle-aged adults (average 59 years) and showed a high rate of malignant transformation (5/9 cases).
• Molecularly, MHAs exhibited HNF1A inactivating mutations with loss of LFABP protein expression.
• Recurrent mutations were identified in GNAS, CDKN1B, and RNF123, genes involved in the protein kinase A (PKA) pathway.

Conclusions:

• Myxoid hepatic adenomas are rare tumors in older individuals with a significant risk of malignant transformation.
• Combined inactivation of HNF1A and mutations within the PKA pathway are key molecular drivers of MHAs.