Clinicopathological investigation of steatohepatitic hepatocellular carcinoma: A multicenter study using immunohistochemical analysis of adenoma-related markers.

Aims: Steatohepatitic hepatocellular carcinoma (SH-HCC) is a newly proposed concept, which shows histological features of steatohepatitis in HCC lesions, and it is strongly associated with metabolic syndrome (MS) and steatosis/steatohepatitis in non-cancerous lesions. Recently, a substantial number of HCC associated with MS were reported to have developed from pre-existing inflammatory hepatocellular adenoma (HCA). To elucidate the characteristic features of SH-HCC, we clinicopathologically investigated strictly diagnosed SH-HCC and non-SH-HCC (standard HCC).

Methods: This was a retrospective multicenter study. A clinicopathological investigation was undertaken to compare 62 cases with SH-HCC features to 31 age- and sex-matched standard HCC cases, including an immunohistochemical study using markers for classification of HCA and diagnosis of HCC.

Results: The characteristic features of SH-HCC compared with standard HCC include a higher rate of complications of MS, more frequent non-alcoholic fatty liver disease as an underlying liver disease, and HCC development in non-cirrhotic liver. The rate of solitary tumors showed no difference between the two groups, but the median diameter of the main tumor was greater in SH-HCCs (45 mm/20 mm, P = 0.01). The HCCs were mostly moderately differentiated, and the patterns were mainly trabecular in both groups. Positive findings for serum amyloid A and C-reactive proteins, classification markers of inflammatory HCA, were significantly higher in cancerous lesions of SH-HCC cases (50%/13%, P < 0.01 and 42%/16%, respectively; P = 0.01).

Conclusions: We confirmed that SH-HCC was strongly associated with MS and NAFLD, and found that classification markers of inflammatory HCA were significantly higher in SH-HCC. Further studies are needed to elucidate the relationship between SH-CCC and HCA for understanding the carcinogenic pathways in these diseases.