An Unusual Radiologic Image of Extensive Tumor Mass Infiltrating Hepatic Hilum without Signs of Cholestasis-A Case Report and a Literature Review of Non-Cancerous Lesions Mimicking Intrahepatic Cholangiocarcinoma.

Background: Mass-forming intrahepatic cholangiocarcinoma (mICC) is the most frequent type of ICC. In contrast-enhanced computed tomography, mICC is visualized as a hypodense lesion with distal dilatation of intrahepatic bile ducts. The presented case illustrates the unusual manifestation of mICC in a 71-year-old male patient, where despite the extensive tumor mass and the hilar infiltration, the dilatation of intrahepatic bile ducts and cholestasis were not noted.

Methods: A literature review on PubMed was performed. Primarily, 547 records were identified, and the titles and abstracts were systematically searched. Regarding the inclusion and exclusion criteria, 31 papers describing the non-cancerous liver lesions mimicking ICC were included in the further analysis.

Results: In 41.9% of the analyzed non-cancerous lesions, the obstruction of the bile ducts was not noted, similar to our patient. A significant cholestasis has been found in 30.03% of analyzed patients. The invasion of the liver hilum was noted in one-third of the patients.

Conclusions: Atypical radiological features in lesions suspected of ICC, such as the absence of intrahepatic bile-duct dilation, are common in benign lesions. In the case of radiologically atypical lesions suspected of ICC, the diagnostic imaging needs to be correlated with clinical data, and the diagnosis should be confirmed with a pathological examination.