Nichtinvasive Bild gebende Diagnostik des cholangiozellulären Karzinoms

Cholangiocellular carcinoma (CCC) is a rare tumor that arises in the biliary ducts and two types can be differentiated, depending on the location: primarily peripheral CCC and extrahepatic or hilar CCC. These two variants differ in macroscopic appearance and in growth pattern. The centrally located CCC is also referred to as “Klatskin” tumor. Various imaging modalities are available for the diagnosis of CCC. To date, endoscopic retrograde cholangio-pancreaticography (ERCP) has been considered the gold standard for this tumor type, even though it is an invasive diagnostic procedure. Increasing numbers of noninvasive techniques have become established as a supplement to ERCP, and in some cases even as an alternative: computed tomography (CT), magnetic resonance imaging (MRI) and magnetic resonance cholangio-pancreaticography (MRCP). Positon emission tomography (PET) in association with CT (PET-CT) is very helpful in detecting or excluding the presence of distant metastases and in following the course of these tumors. MRI and MRCP in particular, provide comprehensive diagnostic information which is comparable and, in some situations complementary, to that yielded by ERCP. The choice of imaging modality depends on the clinical presentation and the level of suspicion of underlying malignant disease. Ultrasound is most effective in providing an overview when the symptoms are vague. If the conditions for the examination are poor or the results of ultrasound are inconclusive, MRCP combined with contrast-enhanced MRI is indicated, so that a reliable diagnosis can be reached quickly and/or the findings can be differentiated from benign pathological findings. If there is a real suspicion that CCC is present or this has already been confirmed, CT might be preferred for comprehensive staging of the primary tumor and of potential distant metastases.