Cholangiocarcinoma: Morphologic classification and ultrasonographic findings

Purpose: According macro morphological features, intrahepatic cholangiocarcinoma is classified into three types: nodular (mass forming), periductal (infiltrating along the bile duct wall) and intraductal (visible intraductal tumor). Extrahepatic cholangiocarcinoma is classified as nodular, sclerosing and papillary, corresponding to intrahepatic types respectively. The aim of the study is to show different ultrasound findings in patients with various morphological appearances of cholangiocarcinoma.

Material and methods: The study shows 35 patients with cholangiocarcinoma. Diagnosis was established by clinical findings, laboratory tests, tumor markers, ultrasound, ERCP, CT, MRI, MRCP and biopsy.

Results: Based on the site of biliary origin, patients are divided in two groups: intrahepatic (8 patients) and extrahepatic cholangiocarcinoma (27 patients).

First group: According the macro morphological appearance there were: nodular (6 patients), periductal (1 patient), and intraductal (1 patient) type. On ultrasound, nodular type presented as solid tumors with heterogeneous pattern, findings not conclusive for diagnosis. Biopsy confirmed cholangiocarcinoma. Periductal type presented with bile duct narrowing in segment VIII and irregularity of the liver parenchyma proximal of the obstruction. Intraductal type presented with tumor mass within the bile duct in the left lobe with segmental bile duct dilatation.

Second group: Based on tumor anatomic location, there were: hilar (22 patients) and on the distal portion of the common bile ducts (5 patients). Concerning macro morphological findings, ultrasound disclosed: nodular type-well defined tumor mass in the liver hilus (6 patients), sclerosing-segmental bile duct narrowing with bile duct dilatation (19 patients) and papillary (intraductal)-visible tumor mass into the bile duct with proximal bile duct dilatation (2 patients).

Conclusion: Morphological classification of cholangiocarcinoma is valuable for the interpretation of different ultrasound imaging features. Combined with other imaging modalities and biopsy, it is useful for accurate diagnosis and differentiation from other tumors and non-tumorous lesions and for predicting prognosis and plannig the surgical approach.