Chronological changes in etiology, pathological and imaging findings in primary liver cancer from 2001 to 2020

Purpose: To achieve a historical perspective, the chronological changes in primary liver cancer over a 20-year period were investigated at a single institution, focusing on shifts in etiology and the impact on imaging and pathological findings using The Liver Imaging Reporting and Data System.

Materials and methods: A retrospective study of surgically resected primary liver cancer in 680 patients from 2001 to 2020 resulted in 434 patients with 482 nodules being analyzed. Dynamic contrast-enhanced computed tomography imaging and the Liver Imaging Reporting and Data System 2018 classification were employed. Two pathologists and two radiologists independently evaluated specimens and images.

Results: This study highlighted a significant decline in cases of viral hepatitis and cirrhosis in primary liver cancer patients but an increase in intrahepatic cholangiocarcinoma and scirrhous hepatocellular carcinoma. Notably, there was a rise in non-viral hepatitis cases, potentially pointing toward an increase in steatohepatitic hepatocellular carcinoma cases in the future. Intrahepatic cholangiocarcinoma, scirrhous hepatocellular carcinoma and steatohepatitic hepatocellular carcinoma tumors exhibited slightly different distributions in the Liver Imaging Reporting and Data System classification compared with ordinary hepatocellular carcinoma, which may reflect the presence of fibrosis and lipid in tumor parenchyma.

Conclusions: Consistent with past reports, this study demonstrated the emergence of primary liver cancer against a backdrop of non-viral and non-cirrhotic liver. Liver Imaging Reporting and Data System has been consistently useful in diagnosing primary liver cancer; however, among the histological subtypes of hepatocellular carcinoma, an increase is anticipated in scirrhous hepatocellular carcinoma and steatohepatitic hepatocellular carcinoma, which may present imaging findings different from those of ordinary hepatocellular carcinoma. This development may necessitate a reevaluation of the current approach for diagnosing and treating hepatocellular carcinoma based solely on imaging.