Diagnosis of intrahepatic cholangiocarcinoma with CEUS.

Intrahepatic cholangiocarcinoma (ICC) is a rare, heterogeneous, highly lethal tumor of the biliary tract. Due to the lack of effective treatments, an early identification of ICC is essential to achieve the best outcome in terms of therapy and prognosis aiming for a curative intent. ICC may arise on a normal liver or with an underlying liver disease, making the diagnosis more difficult and complex. Contrast-enhancement ultrasound (CEUS) is an accurate procedure able to detect ICC-specific contrast vascular pattern, and thus facilitating the correlation between radiological and histopathological findings with high specificity and sensitivity. CEUS has been shown to have a high diagnostic potential in the diagnosis of ICC thanks to the possibility of studying in real time the intralesional microcirculation and evaluating the precocity of the enhancement of the lesion during the arterial phase. All these features allow to differentiate the ICC from hepatocarcinoma (HCC) with high sensitivity and specificity. Furthermore, CEUS is a rapid, non-invasive, non-nephrotoxic or non-allergenic tool. The only limitations CEUS may have are related to the disease site and patient characteristics (obesity) and compliance, including the operator's experience. A clinical evaluation of the patient, together with tumor markers and biochemical tests assessment, to differentiate ICC from HCC are highly suggested.