Immunohistochemical pitfalls in the diagnosis of focal nodular hyperplasia and inflammatory hepatocellular adenoma

摘要

It is clinically important to differentiate focal nodular hyper-plasia (FNH) from inflammatory hepatocellular adenoma (IHCA) because FNH does not need surgical resection. However, these two types of benign liver tumors may share some pathological similarities, at least in some areas. In a recent article published in Modern Pathology [1], authors from three different US academic centers (San Francisco, Baltimore and Seattte) studied the diagnostic utility and limitations of glutamine synthetase (GS) and serum amyloid-associated (SAA) protein immunohistochemistry in the distinction of FNH from IHCA. Standard histology and immunohistochemistry were analyzed in 54 IHCA, 40 FNH, and 3 indeterminate lesions. Their results are summarized in Table 1. Before going into the analysis of the results of this study, it is important to remind that the interpretation of immunohistochemistry (IHC) is based on molecular data [2].