Nine cases of biliary
cystadenocarcinoma of the liver were studied, with emphasis on its clinicopathologic features,
mucin profiles, and immunohistochemical characteristics. In general, the cystic
tumors had protrusions that consisted of well-differentiated
papillary adenocarcinoma cells with or without benign-appearing epithelial elements. In invading or metastatic foci, the
carcinoma cells tended to show distinctive anaplastic changes.
Tumor growth was confined to the cystic lesions in five cases (noninvasive type), whereas in four cases it extended to the hepatic parenchyma or neighboring organs (invasive type). There was a considerable difference between the two groups in terms of prognosis. In fact, the patients included in the group with the noninvasive type had no sign of
tumor recurrence after an appropriate
surgical procedure. With
mucin histochemical and immunohistochemical approaches, positive reactions with
carcinoembryonic antigen,
tissue polypeptide antigen,
carbohydrate 19-9, and Dupan-2 and the predominance of
sialomucin were observed in most cases of biliary
cystadenocarcinoma, indicating a similar cellular nature of
cholangiocarcinoma.