Sonografische Diagnostik des hilären cholangiozellulären Karzinoms mittels Echosignalverstärker

Abstract

Imaging of hilar cholangiocarcinomas (Klatskin tumour) is very difficult as these tumours spread along the bile ducts and are hardly distinguishable from the surrounding liver parenchyma. Improved imaging techniques are useful for diagnosis and monitoring of new treatment strategies like photodynamic therapy. In a prospective study, we investigated whether contrast-enhanced sonography is useful in the imaging of Klatskin tumours. Between 1997 and 2004, 72 patients with suspected Klatskin tumour were admitted to our clinic. 47 patients with histologically confirmed hilar cholangiocarcinomas (Bismuth III/IV) were included in the study and investigated by standard B-mode sonography. Consecutively, patients were investigated by the use of an echo enhancer. 27 patients were investigated by Levovist (power-Doppler sonography, 2nd harmonic imaging, high MI), 20 patients were investigated by Sonovue (CPS, low MI). By use of baseline sonography, visualisation of a tumour and differentiation from normal liver parenchyma was possible in 17 of 47 (36%) patients. After application of contrast agents, tumours showed defects in comparison to the intense flow signal of the surrounding liver tissue during the portalvenous phase and could be discriminated from normal liver tissue allowing determination of tumour size and infiltration of liver parenchyma in all patients (100%). During the arterial phase, 42/47 (89%) of neoplasms showed hypovascularisation compared to surrounding liver tissue, 5/47 (11%) tumours were hypervascularised. During follow-up, metastatic tumour spread was observed in (20/47) 43% of patients, 25/47 (53%) patients developed ascites. Contrast agents allow improved imaging of hilar cholangiocarcinomas. The majority of hilar cholangiocarcinomas are hypovascularised.