A CASE OF HEPATOBILIARY CYSTADENOMA WITH OVARIAN-LIKE STROMA

Abstract

A 52-year-old woman was referred to the hospital because of a cystic lesion in the liver detected by ultrasonography at another hospital. Computed tomography, magnetic resonance imaging and ultrasonography of the abdomen revealed a multilobular cystic tumor 14cm in maximum diameter in the left lobe of the liver. The cystic wall was smooth and thin with partially thickened septum. The serum level of CA19-9 was notably high, 4, 056U/ml. Hepatobiliary cystadenoma or cystadenocarcinoma was diagnosed, and a left lobectomy was performed. In the resected specimen, and encapsulated multilobular cystic mass was measured 14×10×9cm in dimension. Microscopically, the inner layer of the cyst with papillary projections in places was lined by a single layer of mucin secreting columnar epithelium, and the intermediate layer was composed of dense mesenchymal stroma, so-called ovarian-like stroma, interposed between an inner epithelial lining and an outer connective tissue layer. Mucinous biliary cystadenoma with mesenchymal stroma of the liver was diagnosed. The high serum CA19-9 level was normalized. No signs of recurrence have occurred, as of 2years 2months after the operation. Hepatobiliary cystadenoma with ovarian-like stroma is a rare neoplasm with possible malignant transformation. Total excision of the tumor is recommended for hepatobiliary cystadenoma.