Problematic lesions in cirrhotic liver mimicking hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a unique malignancy that can be diagnosed and treated based on non-invasive imaging criteria without histological confirmation in cirrhotic patients, which opens the possibility, although rare, of false-positive diagnosis of the tumor. This brief review illustrates benign and non-HCC malignant lesions arising in cirrhotic liver that could have been erroneously diagnosed as HCC based on imaging criteria: focal nodular hyperplasia-like nodules, serum amyloid A-positive nodules, dysplastic nodules, spontaneously regressing lesions, combined hepatocellular-cholangiocarcinoma, cholangiocarcinoma, sarcomatoid carcinoma, lymphoepithelioma-like carcinoma, hepatoblastoma, and metastatic adenocarcinoma. To determine the potential differences in clinical courses and post-treatment outcome of HCC diagnosed by imaging alone and those histologically, we suggest the terms HCCi and HCCp to distinguish between lesions that are diagnosed as HCC based on imaging alone from those diagnosed based on pathological examination, respectively.Key Points • Benign lesions, such as focal nodular hyperplasia-like nodules, serum amyloid A-positive nodules, dysplastic nodules, and spontaneously regressing lesions, may show imaging findings that mislead to the diagnosis of HCC. • Non-hepatocellular malignant lesions, such as sarcomatoid carcinoma, lymphoepithelioma-like carcinoma, hepatoblastoma, and metastatic adenocarcinomas, can be erroneously diagnosed as HCC based on imaging findings alone, even in cirrhotic liver.