Cystadenoma and cystadenocarcinoma of the liver: localization of carcinoembryonic antigen.

Cystadenomas and cystadenocarcinomas of the liver are rare tumors. The distribution of carcinoembryonic antigen (CEA) in two cystadenomas and a cystadenocarcinoma was examined immunohistochemically by the peroxidase-labeled antibody method, at the light microscopic level. In the cystadenomas and areas consisting of benign-appearing cells in the cystadenocarcinoma, CEA was localized to the luminal surfaces of the glandular cells appearing as thin linear stains. In malignant epithelial cells forming nests and daughter cysts of the cystadenocarcinoma, CEA was demonstrated throughout the cytoplasm, in a diffuse pattern. Thus, the immunohistochemical localization of CEA may be helpful in the diagnosis of borderline lesions and in determining the distribution of benign and malignant epithelium in cystadenocarcinomas. The etiology, clinical features, pathology and treatment of these rare tumors are discussed.