CHOLANGIOCARCINOMA ARISING IN BILE-DUCT ADENOMA WITH FOCAL AREA OF BILE-DUCT HAMARTOMA

A 59-year-old male with history of sigmoid colon cancer had a high ser um-CEA level and was referred for the evaluation of metastatic liver d isease. Ultrasonography and computerized tomography showed two tumours in the liver. Macroscopically, these were in segment 4 (S4) and 2 (S2 ). Histologically, the tumour in S4 showed a number of bile ductules w ith variable amounts of stroma, an appearance compatible with bile duc t adenoma (BDA). There were markedly atypical ductules of various size s, the epithelium of which had coarsely granular/hyperchromatic large nuclei, in some areas of the lesion. These atypical ductules showed in vasive growth into the liver parenchyma. Some cystically dilated ductu les with bile plugs resembling bile duct hamartoma (BDH) were also see n. The other tumour in S2, was a metastatic adenocarcinoma from sigmoi d colon and showed strongly positive staining for CEA. Since the lesio n in S4 of our case is solitary and most of histological features are similar to those of BDA with markedly atypical bile ductules, we consi der that this may be the first case of cholangiocarcinoma associated w ith BDA with focal area of BDH. It is possible that the adenoma-carcin oma sequence occurs in biliary tumours.