Contrast enhanced ultrasound in mixed hepatocellular cholangiocarcinoma: Case series and review of the literature

BackgroundMixed hepatocellular cholangiocarcinoma is a rare form of primary liver cancer.AimsThe aim of this study is to report the results of the use of contrast enhanced ultrasound in a series of patients with confirmed mixed hepatocellular cholangiocarcinoma and to provide an updated literature review.MethodsBetween January 2012 and October 2016, 25 Asian patients with confirmed mixed hepatocellular cholangiocarcinoma were included in this bicentric retrospective analysis. Clinical data as well recorded images of a standardized conventional B-mode ultrasound and contrast-enhanced ultrasound examination were interpreted by two blinded, independent, experienced radiologists in consensus.ResultsAll mixed hepatocellular cholangiocarcinoma lesions were heteroechoic on B-mode ultrasound, with ill-defined margins and irregular shapes. Arterial phase hyperenhancement was present in all 25 patients. Late-phase washout and hypoenhancement was present in 24/25 (96%) patients. However, rim-enhancement and early wash-out (which are common in cholangiocellular carcinoma) were found in over 60% of the cases.ConclusionContrast-enhanced ultrasound demonstrated findings not typical for HCC in a large proportion of patients with confirmed mixed hepatocellular cholangiocarcinoma. Therefore, histological confirmation is crucial, especially in lesions with atypical findings.